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Atkin, Ian L. "Dynamics of SQUIDs and multiple SQUID arrays." Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/666.
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Schön, Pieter-Jan. "An investigation into the influence of the environment on spawning aggregations and jig catches of chokka squid Loligo Vulgaris reynaudii off the south coast of South Africa." Thesis, Rhodes University, 2000. http://hdl.handle.net/10962/d1016369.
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Erratic and highly variable catches in the South African chokka squid Loligo vulgaris reynaudii fishery, cause socio-economic hardship for the industry and uncertainty for resource managers. Catch forecasting can reduce this problem as it is believed that catch variability is strongly influenced by environmental factors. In this study, data were collected at varying temporal and spatial scales. Data for the hourly time-scale study were collected from 1996-1998, aboard commercial vessels, whilst for the longer time-scales, data were extracted for Kromme Bay (a single fishing area) from existing databases (1991-1998) that were comprised of compulsory catch returns and oceanographic data. The environment-catch relationship for chokka squid on the inshore spawning grounds was then investigated using multiple correlation and regression analysis, analysis of variance, contingency table analysis and cross-correlation statistical techniques. This simple, direct, 'black box' statistical approach was relatively successful in developing a predictive capability. On a short time-scale (hourly), the regression model accounted for 32% of the variability in catch, with turbidity the main determinant (13%). On a daily monthly time-scale, the best prediction model was on a monthly scale, accounting for 40% of the variability in catch. The principal determinant, bottom temperature anomaly (11 %), was found to lag one month forward. Seasonal and diel catch variations induced changes in the relative importance of turbidity, water temperature and wind direction on catches. A strong, positive relationship was found between easterly winds (which cause upwelling) and catch, particularly in summer. Catch rates, however, decreased with an increase in turbidity. The correlation between temperature and catch was generally negative, however, higher catches were associated with a temperature range of 13-18°C. Highest catch rates were associated with easterly winds, zero turbidity conditions and sea surface temperatures from 15.0-16.9°C. Selected case studies (in situ observations) suggested that upwelling and turbidity events act as environmental triggers for the initiation or termination of the spawning process, respectively. A holistic approach is required to improve predictive capability of chokka squid abundance. Although short-term predictability remains essential (i.e. hourly-scale), future research should concentrate on long-term prediction models (e.g., monthly time-scales) involving greater spatial variation, which are the most important for management.
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Choi, Kin-sang. "Reproductive biology and ecology of the loliginid squid, Uroteuthis (Photololigo) duvauceli (Orbigny, 1835), in Hong Kong waters." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39557169.
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Yu, D. B. (Daniel Byungyoon) 1976. "Electronic characteristics of SQUIDs." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/10148.
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蔡健生 and Kin-sang Choi. "Reproductive biology and ecology of the loliginid squid, Uroteuthis (Photololigo) duvauceli (Orbigny, 1835), in Hong Kong waters." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39557169.
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Wong, Ying-yee. "The squid jigging industry in Hong Kong /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37563324.
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Colman, P. D. "Design, characterisation and optimisation of high Tc dc SQUIDs." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597881.
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Superconducting Quantum Interference Devices (SQUIDs) are the most sensitive magnetic flux sensors known. In order to achieve a high field resolution, an antenna is coupled to the bare SQUID. Flux focusing, direct and flux transformer coupling schemes were investigated. Off-axis pulsed laser deposited YBa2Cu3O7-δ films with protective SrTiO3 (STO) cap layers on 24° STO bicrystal substrates were patterned into SQUID structures. A multilayer technology with YBCO and STO layers was used to fabricate trilayer flux transformers. The flux transformers was then coupled inductively to the bare SQUID in a flip-chip arrangement. Characterisation equipment was developed to measure SQUID parameters. Noise measurements with a bias reversal technique were employed to reduce the 1/f component, which dominates the noise at low frequencies. All noise data were obtained at 77 K. For a flux focusing SQUID, a flux noise level of φn = 2.8 μφ0Hz-1/2 at 10 kHz and φn = 11.5 μφ0Hz-1/2 at 1 Hz with bias reversal was achieved. The field sensitivity of the flux focused SQUID was limited by the small effective area, Aeff = 0.83 x 10-3 mm2, but this type of device was successfully integrated into the IRC cold sample scanning SQUID microscope which was used to image currents in wires and ferromagnetic link samples. Direct and flux transformer coupling schemes increased the effective areas to 0.23 mm2 and 1.08 mm2 respectively. The best white field sensitivity measured corresponded to 105 fTHz-1/2 for the directly coupled SQUID and 42 fTHz-1/2 for the flux transformer coupled SQUID. Planar, first-order directly coupled gradiometers were investigated as part of the collaboration with Oxford Instruments plc and a white gradient field sensitivity of 2.1 pTcm-1Hz-1/2 in an unshielded environment was achieved.
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Collot, Romain. "Etude d’une tête de réception hyperfréquence en technologie supraconductrice." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENT043.
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Les systèmes de télécommunication de type radio logicielle ou "Software Defined Radio" (SDR) exploitent les techniques numériques qui permettent leur reconfigurabilité, que ce soit en termes de fréquence, de bande passante utilisée, ou de méthode de modulation/démodulation des signaux. Ceux-ci nécessitent des architectures permettant la numérisation des signaux analogiques RF à des fréquences d'échantillonnage de plusieurs dizaines de GHz, avec des bandes passantes de plusieurs dizaines de MHz et une résolution supérieure à 10 bits. Ces objectifs sont très difficiles à atteindre avec la technologie actuelle des semi-conducteurs. La logique à quantum de flux magnétique ou logique "Rapid Single-Flux-Quantum" (RSFQ) se présente comme un candidat séduisant pour la conception de tels systèmes.En effet, celle-ci permet d'atteindre des fréquences d'horloge de plusieurs centaines de GHz pour une consommation d'environ 100 nW par porte logique. Le travail de thèse a consisté en la réalisation d'un prototype de chaîne de réception RF analogique-numérique en technologie RSFQ. L'étude et la conception des différents blocs la constituant comme le convertisseur analogique-numérique et ceux de traitement du signal numérisé en aval a été réalisée. Les premiers résultats expérimentaux confirment la fonctionnalité des cellules RSFQ de base constituant le bloc de traitement numérique. La difficulté à faire fonctionner expérimentalement les blocs plus complexes a soulevé la question de la sensibilité des cellules RSFQ aux perturbations magnétiques extérieures. Cette problématique a été étudiée sur des circuits RSFQ simples et a permis de conclure qu'un champ magnétique externe de quelques dizaines de $mu$T était suffisant pour dégrader le fonctionnement de tels circuits. Une solution de prise en compte des effets d'un champ magnétique externe dans le simulateur utilisé a été développée pour anticiper ces problèmes dès la conception. Celle-ci a été validée expérimentalement avec un Superconducting Quantum Interference Device (SQUID)Information and telecommunication Software Defined Radio (SDR) systems are mainly based on digital techniques, which enable to easily reconfigure them, in terms of frequency, bandwidth and modulation techniques. They can process the information entirely in a digital way, by directly sampling the input RF signal and require analog-to-digital converters with strong performances. Indeed, SDR systems have to work at sampling frequencies of several tens of GHz, with large bandwidths and a suitable resolution ($geq$ 10 bits). Rapid-Single-Flux-Quantum logic (RSFQ) seems to be an interesting solution to design such systems. This technology can reach clock frequencies of several hundreds of GHz with a power consumption of only 100 nW per logic gate. This work deals with the design of a superconductive RF front-end receiver based on RSFQ technology. The study of the different parts of the chain was done, such as the analog-to-digital converter and the signal processing part of the digital signal. Experimental results confirm that all simple RSFQ cells work with correct margins. Complex circuits work with more difficulty, raising the issue of the sensitivity of RSFQ cells to external magnetic disturbances. This point was studied on basic RSFQ cicuits and shows that a magnetic field of about 10 $mu$T is sufficient to spoil the operation of the circuit. Moreover, a solution to take into account magnetic effects in the simulation of the circuits was developed and experimentally validated on a Superconducting Quantum Interference Device (SQUID)
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Bruno, Antonio Carlos Oliveira. "Gradiômetros supercondutores acoplados a SQUIDs e sua aplicação em biomagnetismo." Universidade de São Paulo, 1990. http://www.teses.usp.br/teses/disponiveis/54/54132/tde-19052009-095436/.
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O objetivo desta tese foi o estudo da detecção de campos magnéticos fracos através da utilização de gradiômetros supercondutores acoplados à SQUIDs e sua aplicação ao biomagnetismo. Um novo modelo teórico para descrição do gradiômetro foi desenvolvido com a obtenção da sua função de transferência espacial. Através desta função de transferência a atuação do gradiômetro sobre os sinais detectados pode ser quantificada. Além disso, foi desenvolvido para a medida experimental da função de transferência, onde as imperfeições no processo de construção do sensor podem ser medidas e avaliadas. Foi proposta uma nova terminologia para descrição do gradiômetro ao invés de sua descrição física. Nesta terminologia, o gradiômetro ficará especificado pelo seu roll off, freqüência de corte espacial e ganho máximo. Também foi generalizado o método para projeto de gradiômetros onde novas configurações podem ser construídas e testadas. A partir da obtenção desta função de transferência um método para calibração tesla /volt do sistema foi desenvolvido, com uma precisão até então não alcançada por outros métodos e perfeitamente apropriado para utilização em sistemas multicanais. Finalmente foi desenvolvido um algorítimo de desconvolução para, a partir de sinais detectados com gradiômetros planares, recuperar o sinal original como ele tivesse sido detectado somente por uma bobina. Este algorítmo também pode ser utilizado para auxílio no projeto de arrays destes gradiômetros.The objective of this thesis was to study the detection of weak magnetic fields through the use of superconducting gradiometers coupled to SQUIDs and its application to biomagnetism. A new theoretical model for the specification of the gradiometer was developed by obtaining its spatial transfer function. Through the transfer function the signal detected by the gradiometer can be quantified. Besides, a procedure was developed to experimentally measure the spatial transfer, where the imperfections in the construction process of the sensor can be measured and evaluated. A new terminology was proposed for specification of the gradiometer instead of his physical description. Using this terminology, the gradiometer will be specified by its roll off, spatial cutoff frequency and maximum gain. Also the method was generalized for design of gradiometers where new configurations can be built and tested. From the transfer function a method for tesla/volt calibration of the system was developed. Finally a deconvolution algorithm was developed, that from signals detected by the gradiometer the original signal can be recovered. This algorithm also can be used in the design of gradiometer arrays.
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Gerra, Guido. "Electromagnetic modelling of superconducting sensor designs." Thesis, University of Cambridge, 2003. https://www.repository.cam.ac.uk/handle/1810/104788.
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The problem of design optimisation of thin film direct current Superconducting QUantum Interference Device (SQUID) magnetometers made of YBCO (YBa2Cu3O7-x) was considered. The inductances and effective areas were calculated using the software package 3D-MLSI. Resolution and reliability issues were first tested on simple superconducting systems, showing good agreement with analytical formulae and experimental results, and demonstrating that a remarkable precision can be obtained though at the expense of CPU time and memory. The software was then used to simulate a SQUID magnetometer fabricated in the Device Materials Group of the Department of Materials Science and Metallurgy, proving that 3D-MLSI can be used to predict the parameters of real systems with acceptable accuracy.
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Van, der Vyver Johan Samuel Frederik. "The geographic stock structure of chokka squid, Loligo Reynaudi, and its implications for management of the fishery." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1012973.
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It is currently hypothesised that the chokka squid (Loligo reynaudi) consist of a single stock. This was tested through a spatial comparison of the morphology of this species. Forty three morphometric characters were measured from 1079 chokka squid collected from three regions: the south coast of South Africa, the west coast of South Africa, and southern Angola. While no significant differences were found for the hard body parts, results from discriminant function analyses showed the soft body morphometric characters from each of the three regions differed, with an overall correct classification rate of 100% for males and 99% for females in all three regions. Due to the existing model being used to assess the resource currently being updated it was not feasible to apply this model to the area-disaggregated data from this study. Rather, the CPUE trends and catches from the area-disaggregated data were compared against those of the area-aggregated data, as a first attempt to discern any appreciable differences which would suggest the use of disaggregated data in future assessments. Both the trawl and jig CPUE trends from the area-disaggregated analysis differed only slightly from those of the area-aggregated data. Similarly, the spring and autumn biomass trends for the main spawning area (east of 22°E) followed the same trends as for the full area. It is therefore concluded that there is currently no need to assess the resource on an area-disaggregated basis.
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Downey, Nicola Jean. "The effect of temperature and turbidity on spawning chokka squid, loligo reynaudii, in Eastern Cape waters." Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/945.
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Several studies suggest the environment influences chokka squid catches which are mostly based on the successful formation of inshore spawning aggregations. None of the evidence, however, is direct observation. Acoustic telemetry offers a means to determine the response of spawners to changes in the environment and insight into the behaviour of spawning squid. A hexagonal array of VR2 receivers deployed 500 m apart was deemed to be ideal to monitor the movement patterns of squid on the spawning sites. In isothermic conditions, an area up to 1.28 km2 could be monitored as there was an approximate 50 m overlap in individual VR2 receiver range. In thermocline conditions however, “acoustic dead zones” as wide as 350 m may have existed between VR2 receivers, limiting the performance of this configuration. Similarly benthic turbidity events would also decrease detection range and limit performance. A hexagonal array of VR2 receivers was moored in Kromme Bay on and around active spawning aggregations during the squid fishery closed seasons of November 2003, 2004, 2005 and 2006. Squid were caught on jigs and tagged with V9 acoustic pressure telemetry transmitters. A total of 45 animals were tagged. Presence-absence analysis identified three general behaviours: (1) arrival at dawn and departure after dusk, (2) a continuous and uninterrupted presence for a number of days and (3) presence interrupted by frequent but short periods of absence. Overall, the data suggests frequent migrations between spawning aggregations and offshore feeding grounds. The pressure sensor data showed both males and females stayed persistently near the seabed during the day, but at night, this pattern was broken with common activity higher up in the water column. The squid did not remain exclusively in the water column and regularly made excursions to the seabed. CTD and temperature data indicated the intrusion of a cold bottom layer due to upwelling at the monitored spawning sites on a number of occasions. The formation of spawning aggregations appears to be triggered by upwelling events and spawning behaviour, once initiated, disrupted by upwelling events with a rapid onset, possibly due to an inability to adapt physiologically over such a short time period.
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Kempf, Sebastian [Verfasser], and Christian [Akademischer Betreuer] Enss. "Entwicklung eines Mikrowellen-SQUID-Multiplexers auf der Grundlage nicht-hysteretischer rf-SQUIDs zur Auslesung metallischer magnetischer Kalorimeter / Sebastian Kempf ; Betreuer: Christian Enss." Heidelberg : Universitätsbibliothek Heidelberg, 2012. http://d-nb.info/1179785770/34.
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Guillaume, Alexander [Verfasser], and Meinhard [Akademischer Betreuer] Schilling. "SQUIDs für die Charakterisierung magnetischer Nanoteilchen / Alexander Guillaume ; Betreuer: Meinhard Schilling." Braunschweig : Technische Universität Braunschweig, 2015. http://d-nb.info/1175819425/34.
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Rottier, P. A. (Pieter Adriaan). "Establishing a process for the fabrication of high-quality HTc SQUIDs." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52828.
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Thesis (MScEng)--University of Stellenbosch, 2002.ENGLISH ABSTRACT: High-temperature (HTc) SQUID magnetometers are used in the biomedical field of magnetocardiography (MCG). The use of MCG enables a much earlier diagnosis of potentially dangerous conditions than the use of electrocardiography (EeG). For the use of MCG, high-quality HTc SQUIDs are necessary. These SQUIDs can only be realised if the design and fabrication processes are well defined and understood. In this thesis an extensive literature review on the design process explains all the concepts necessary to understand and design a high-quality HTc SQUID. Then the fabrication process is redefined and characterised. The SQUIDs are fabricated with YBCO thin films on MgO substrates. The relevant steps in the process are the pulsed laser deposition (PLD), UV lithography and argon ion milling. The characterisation of the fabrication process is based on a statistical method called Design of Experiment (DOE). This enables more information to be obtained about the fabrication process than before. For the PLO process the important parameters are determined and an initial optimisation is done. During the characterisation process it is proven that the use of ozone during PLO has a positive effect on the quality of the YBCO thin film. On the PLD apparatus the substrate heater and laser-beam profile is improved. The UV lithography process is analysed and a DOE is proposed for optimisation. A temperature bath is added to the process to enable better reproducibility. An rf multicusp ion mill is built for argon-ion milling, this device is tested and shown to provide the required etching capability.
AFRIKAANSE OPSOMMING: Hoë-temperatuur (HTc) SQUID magnetometers word in die biomediese rigting vir magnetokardiografie (MKG) gebruik. Met MKG kan 'n mens potensieel gevaarlike toestande heelwat vroeër diagnoseer as wat moontlik is met elektrokardiografie (EKG). HTc SQUIDs van hoë kwaliteit word benodig vir MKG. Sulke SQUIDs kan slegs vervaardig word as die vervaardiging en ontwerpsprosesse goed gedefinieer en verstaan word. In hierdie tesis verduidelik 'n omvattende literatuurstudie oor die ontwerpsproses al die konsepte wat nodig is om 'n SQUID van hoë kwaliteit te verstaan en te ontwerp. Verder word die vervaardigingsproses geherdefinieer en gekarakteriseer. Die SQUIDs word vervaardig met YBCO-dunfilm op MgO-substrate. Die relevante stappe tydens die vervaardiging is: gepulseerde laser deposisie (PLO), UV-litografie en argon-ioonstraling. Die karakterisering van die vervaardigingsproses is gebaseer op 'n statistiese metode genaamd "Design of Experiment" (DOE). Hierdie metode laat 'n mens toe om meer inligting oor die proses te verkry as wat voorheen moontlik was. Gedurende die karakterisering word bewys dat die gebruik van osoon gedurende die PLO-proses 'n positiewe invloed op die kwaliteit van die YBCO-dunfilm het. Die PLO-apparaat se substraatverwarmer en laserstraalprofiel word verbeter. Die UV-litografieproses word geanaliseer en 'n DOE word voorgestel vir die optimisering daarvan. Daar word 'n temperatuurbad by die proses gevoeg om die herhaalbaarheid te verbeter. 'n "Rf multicusp ion mill" word gebou, die toestel word getoets en daar word aangetoon dat dit die nodige etsvermoë het.
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Migliaccio, Claire. "Passifs fonctionnels en technologie supraconductrice HTc : applications aux SQUIDs couplés HF." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0020.
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Les squids (superconducting quantum interference device) sont des dispositifs supraconducteurs utilises, entre autres, en capteur de flux magnetique. Grace a leur extreme sensibilite (possibilite de detecter des champs magnetiques de 10 ft/hz a 1 hz)) ce sont les detecteurs les plus performants a l'heure actuelle. Notre etude porte sur la possibilite d'utiliser les capteurs a squids pour des applications ou la frequence de fonctionnement est de l'ordre du ghz (compatibilite electromagnetique, amplificateur pour l'instrumentation tres haute performance). Neanmoins leurs performances aux frequences elevees sont conditionnees par les elements passifs necessaires a la realisation des dispositifs a squid par integration. Il s'agit essentiellement de boucles supraconductrices de grande dimension et d'inductances planaires possedant un nombre de tours eleve. Ces derniers sont constitues de lignes de transmission associant les effets fonctionnels (pour nous inductifs) aux effets parasites (pour nous capacitifs). Nous modelisons l'ensemble des elements passifs en utilisant un solveur electromagnetique base sur la resolution des equations integrales de maxwell a l'aide de la methode des moments. Apres avoir valide notre methodologie sur des lignes supraconductrices en technologie coplanaire jusqu'a 0,96 t#c et 30 ghz, et sur des inductances planaires conductrices, nous interpretons le comportement frequentiel du squid couple. Nous en deduisons des formules de conception assistee par ordinateur ainsi qu'une procedure d'optimisation generale qui nous permet d'atteindre les frequences de fonctionnement requises
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Lechéa, Nazim. "Étude et réalisation d'un dispositif de résonance magnétique nucléaire à bas champ magnétique en environnement ouvert et bruyant." Paris 6, 2013. http://www.theses.fr/2013PA066124.
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Ce travail porte sur l'étude et la réalisation d'un dispositif de Résonance Magnétique Nucléaire (RMN) sous faibles champs magnétiques dans un environnement non blindé. Il se situe dans le cadre de la physique instrumentale avec pour application l'étude des matériaux par spectroscopie, l'imagerie médicale et l'aide au diagnostic. La RMN est une technique puissante permettant de sonder le cœur de la matière et d'étudier sa structure et ses propriétés moléculaires de façon non destructive et non invasive. Durant ce travail, un dispositif de RMN à bas champ a été étudié et réalisé. Effectuer des mesures à bas champ magnétique permet d'utiliser des aimants plus simples, moins coûteux et de limiter les courants de Foucault dans les matériaux conducteurs. Cependant, à bas champ magnétique, les signaux sont très faibles en raison de la forte dépendance du signal de RMN à l'intensité du champ magnétique lorsqu'une détection par induction magnétique est utilisée. Pour réduire cette dépendance, un SQUID fonctionnant à basse température critique a été utilisé afin d'obtenir une meilleure détection des signaux. Le SQUID a été combiné avec différents types de gradiomètres dont l'objet est de favoriser le signal provenant de l'échantillon par rapport aux signaux produits par des sources parasites lointaines. Il a été démontré qu'une configuration planaire est plus avantageuse qu'une configuration axiale en utilisant une approche analytique basée sur le principe de réciprocité. La chaîne de mesure comprend également un interrupteur supraconducteur astucieux développé dans le cadre de cette thèse. Il sert à protéger le SQUID pendant la phase de magnétisation de l'échantillon et permet d’éviter un temps mort pendant la phase d'acquisition de signal. La technique employée permet de piloter précisément toutes les phases de la mesure sans apporter significativement du bruit. Le dispositif expérimental final a permis de mesurer des signaux de RMN émanant d'un échantillon d'eau dans un environnement totalement ouvert, sujet à différents types de bruits basse fréquence (50 Hz et ses harmoniques, transformateurs, voiture en mouvements, ascenseurs. . . ). Pour cela, une électronique de mesure généraliste contrôlant les différentes séquences de RMN a été réalisée et des méthodes de traitement de signaux analogiques et numériques ont été utilisées. Les protons d'hydrogène sont pré-polarisés dans un champ moyen de l'ordre de 100 mT et leur relaxation est mesurée en champ faible d'environ 50 µT en présence du champ terrestre à des fréquences de quelques kilohertzThis work is focused on the study and the implementation of an experimental device for Nuclear Magnetic Resonance (NMR), under weak magnetic fields in an unshielded and open environment. It takes place within a broader context of instrumental physics, such as materials spectroscopy, medical imaging and diagnostic assistance. NMR is, for this purpose, a powerful technique to probe the heart of the matter, study its structure and molecular properties in a non-destructive and non-invasive way. In this work, an experimental device for low field NMR application has been studied. Using low magnetic field offers the possibility to use much simpler and less expensive magnets, as well as limits eddy currents in conductive materials and promotes the differences between biological tissues in Magnetic Resonance Imaging application. However, at low field, signals are very weak due to the strong dependence of the NMR signal on magnetic field strength when using conventional detection coil. To reduce this dependence and to obtain sufficient signal detectability, a SQUID operating at low critical temperature is used. The SQUID is combined with different types of gradiometer, whose purpose is to promote the sample signal from signals produced by distant spurious sources. By using analytical approach based on reciprocity principle, it was also shown that a planar configuration is more advantageous than axial configuration. The measurement system comprises also a superconducting switch, controlled by laser pulses via an optical fiber, which has been completely designed and developed during this thesis. It is used to protect the SQUID during the sample magnetization, to avoid dead time during signal acquisition phase and to control precisely all NMR sequences without adding much noise to the measurement device. The final experimental device was used to measure NMR signals from water sample, in a fully open environment under the influence of different types of low frequency noises (50 Hz and its harmonics, transformers, cars moving, elevators. . . ). For this purpose, low field NMR electronic was performed for acquiring signal and driving process. In addition, analog and digital signal processing methods were carried out. Hydrogen protons are pre-polarized under about 100 mT, while the relaxation is measured at very small field around 50 µT in the presence of the earth magnetic field giving frequencies around a few kilohertz
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Downey, Nicola Jean. "The role of the deep spawning grounds in chokka squid (Loligo reynaudi d'orbigny, 1845) recruitment." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011867.
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It was previously thought that the South African chokka squid Loligo reynaudi is exclusively an inshore, shallow water spawner. Although spawning mostly within shallow bays (<60 m) the presence of squid eggs in trawls at depths up to 130 m indicates this species frequently makes use of deeper spawning areas on the mid-shelf. The extent of mid-shelf spawning (referred to as deep spawning) and the contribution to recruitment has yet to be assessed. Studies have shown mid-shelf bottom temperature to vary considerably from those inshore, suggesting chokka squid spawn in two very different oceanographic environments. Considering these apparent environmental differences, what leads to the mid-shelf environment becoming a suitable spawning habitat? Does a suitable benthic habitat, required for the attachment of egg pods, occur on the mid-shelf? These questions are not only important for determining the extent of deep spawning, but also to the understanding of factors “driving” deep spawning. The fate of deep spawned hatchlings is another unknown. It has been proposed that the main chokka squid inshore spawning grounds are positioned to exploit the net westward currents on the Eastern Agulhas Bank, i.e. paralarvae would be transported west from the hatching site to the cold ridge, an area of high primary and secondary productivity on the Central Agulhas Bank. This concept has come to be known as the Western Transport Hypothesis. Lagrangian ROMS-IBMs (regional ocean model system – individual-based model) predict the net westward transport of paralarvae from both the inshore and deep spawning grounds, to the cold ridge. These simulations were used to investigate the transport of hatchlings to the cold ridge feeding grounds before the exhaustion of yolk reserves. The fate of paralarvae on reaching the feeding grounds has not yet been investigated. This work has contributed new knowledge to our understanding of deep spawning and its role in recruitment. Specific aims of this study were to (1) determine the extent, range and importance of the deep spawning grounds relative to those inshore; (2) investigate the deep spawning ground habitat (Agulhas Bank mid-shelf) morphology and oceanographic environment; (3) determine the transport and survival of deep spawned hatchlings; and (4) investigate the origin and distribution of chokka squid paralarvae on the Agulhas Bank. The extent, depth range and importance of the deep spawning grounds, relative to those inshore was assessed using 23 years of demersal trawl survey data. Data for both the west and south coasts of South Africa were examined for egg capsules. No spawning was found on the west coast. Data showed that chokka squid preferred the Eastern Agulhas Bank for spawning. Spawning occurred not only inshore but also on the mid-shelf extending to depths of 270 m near the shelf edge. The majority of deep spawned eggs however, were found in the depth range 71-130 m. Squid egg density markedly decreased beyond 70 m, suggesting delineation between the inshore and deep spawning grounds. Total egg biomass calculations for depths shallower and deeper than 70 m indicated the coastal area to be strongly favoured, i.e. 82 vs. 18%. These results contest the commonly accepted notion that chokka squid is an inshore spawner and redefine the spawning grounds to extend across the shelf. Apart from an initial study investigating bottom temperature on the mid-shelf, very little is known about the deep spawning habitat. St Francis Bay, a commonly used spawning location, was chosen as a demonstration area for further study. The deep spawning grounds (71-130 m) were mapped and benthic habitat described from underwater video footage. A study investigating cross-shelf bottom conditions was undertaken off Thys Bay. CTD data were used to compare seasonal bottom temperature and oxygen on the St Francis Bay inshore and deep spawning grounds. Squid movement between the two spawning habitats was assessed using filament tagging. Predation and fishing pressure across the spawning grounds was reviewed. The mid-shelf benthic habitat was found to be similar to that inshore and available for spawning. Despite the generally colder bottom temperatures on the mid-shelf, this study showed that bottom temperature in deeper waters can at times be warmer than inshore. Although mid-shelf warming events lasted from a few hours to a number of days, they resulted in similar conditions to those on the inshore spawning grounds. It is likely these events act to expand or shift spawning habitat. The movement of squid between the two spawning habitats makes it possible for them to seek patches of warm bottom water with appropiate substrate. This suggests they are spawning habitat opportunists. Predation and fishing pressure appear to be higher on the inshore spawning grounds. It is feasible that this also forces spawners to seek out more favourable habitat offshore. An individual-based model was used to predict the fate of mid-shelf and inshore hatched paralarvae. Within the model, both the highly productive cold ridge and inshore spawning grounds were considered feeding or nursery areas. Paralarvae were released from six inshore and six deep spawning sites, spanning the coast between Port Alfred and Knysna. All paralarvae not reaching the feeding areas before the exhaustion of yolk-reserves (≤5 days), not retained within the feeding grounds (≥14 days), and not retained on the Agulhas Bank after exiting the feeding grounds were considered lost. This work illustrated the dependence of paralarval transport success on both spawning location and time of hatching, as established in earlier studies. The current IBM has expanded on initial work, emphasizing the importance of the cold ridge and inshore spawning grounds as nursery areas for deep and inshore spawned paralarvae, respectively. This work has highlighted the complex interactions between processes influencing recruitment variability for chokka squid. Possible relationships between periods of highest recruitment success and spawning peaks were identified for both spawning habitats. Based on the likely autumn increase in deep spawning off Tsitsikamma, and the beneficial currents during this period, it can be concluded deep spawning may at times contribute significantly to recruitment. This is particularly true for years where the cold ridge persists into winter. Data on chokka squid paralarval distribution are scarce. Paralarval distribution and abundance, in relation to Agulhas Bank oceanography, was investigated using bongo caught paralarvae and corresponding oceanographic data. Individual-based models (IBMs) were used to predict the origin or spawning site of the wild caught paralarvae, with reference to inshore versus deep spawning. Although failing to predict realistic points of origin, this study provided evidence to support a number of scenarios previously assumed to influence chokka squid recruitment. First is the possible influence of coastal upwelling on the retention, and hence spatial distribution, of paralarvae on the inshore spawning grounds. The second factor thought to impact recruitment is the loss of paralarvae from the Agulhas Bank ecosystem. This study confirmed the removal of paralarvae from the Eastern Agulhas Bank due to Agulhas Current boundary phenomena and resultant offshelf leakage. In addition, data suggested that the formation of the cold ridge could enhance retention on the Central Agulhas Bank, and so prevent offshelf leakage from the Central and Western Agulhas Bank. A synthesis of the main conclusions is presented. Implications of the findings and directions for future research are discussed.
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Graf, zu Eulenburg Alexander. "High temperature superconducting thin films and quantum interference devices (SQUIDs) for gradiometers." Thesis, University of Strathclyde, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366689.
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Recoba, Pawlowski Eliana. "Réseaux de SQUIDs à haute température critique pour applications dans le domaine des récepteurs hyperfréquences." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS121/document.
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Les circuits à base de jonctions Josephson comme les filtres à interférences quantiques, nommés SQIF (Superconducting Quantum Interference Filter), sont des capteurs très sensibles au champ magnétique. Les éléments de base d’un tel circuit sont les SQUID (Superconducting Quantum Interference Device). Aussi performants dans la détection de champ magnétique, ces derniers ne permettent pas de réaliser des mesures absolues. De plus, la nécessité d’un asservissement par une boucle à verrouillage de flux limite la bande de fréquence d’utilisation. Les SQIF n’ont pas cette limitation et permettent les mesures absolues de champ magnétique. Leur capacité à combiner une taille compacte, une très bonne sensibilité et une large bande fréquentielle d’utilisation fait de ces capteurs des sérieux concurrents aux antennes classiques. Des mesures expérimentales avec des SQIF HTS faits par la technologie de jonctions irradiées montrent qu’il est possible de réaliser la détection de signaux radiofréquence jusqu’au moins 5 GHz en configuration de champ proche et en environnement non magnétiquement blindé. Afin de réaliser l’adaptation d’impédance et améliorer les caractéristiques DC de ces capteurs, différentes géométries de réseau sont étudiées. L’étude permet de définir les paramètres d’importance dans la conception de circuits SQIF afin de réaliser des détecteurs radiofréquence performantsSuperconducting Quantum Interference Filters (SQIF) are Josephson circuits very sensitive to magnetic field. They are made of arrays of SQUIDs (Superconducting QUantum Interference Devices). The latter, when operated alone, doesn’t allows absolute magnetic field measurements and have to be used with a flux locked loop, which limits the frequency band of operation. SQIFs doesn’t have such limitations and they offer the possibility to combine compactness, sensitivity and wide band of frequency at the same time. Because of this, SQIFs are serious concurrents to classical antennas in microwave applications. Experimental measurements made with HTS SQIFs and irradiated Josephson junctions shows that it is possible to detect microwave signals up to 5 GHz in an unshielded environment, and near field configuration. To perform better detection, it is important to match impedance of circuits. In the goal to do this and to improve DC characteristics, different network geometries are studied. At the end this study allows to define which parameters are important in the design of SQIF circuits for microwave detection
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Olyott, Leonard James Henry. "A description of spatial and temporal aspects of the lifecycle of chokka squid Loligo vulgaris reynaudii on the inshore spawning grounds and Agulhas bank off the South Coast of South Africa." Thesis, Rhodes University, 2002. http://hdl.handle.net/10962/d1005096.
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The chokka squid, Loligo vulgaris reynaudii, is a commercially important species supporting a large, high-value export fishery for South Africa. This study reviewed its population dynamics and reproductive biology. Biological information collected on biannual research cruises from September 1986 to April 1999 on the Agulhas Bank as well as information from commercial vessels operating in the inshore environment collected between April 1988 and July 1989 and again between June 1999 and May 2000 were analysed. Size ranges of juveniles, subadults and adults were calculated and used to determine seasonal distribution and abundance patterns. Based on Gonadosomatic Indices (GSI) and percentages of mature squid in each month, two peak reproductive seasons in summer and winter were identified although mature squid were present all year round. Seasonal peaks in sex ratio were also apparent with males outnumbering females by up to 4:1 in the peak-breeding season. The size at which squid matured, demonstrated both spatial and temporal patterns. Squid caught in spring matured at a smaller size than squid caught in autumn and at successively smaller sizes from west to east across the Agulhas Bank. Size at maturity was highly variable especially in males where “sneaker males” were evident in both seasons. Length-to-weight linear regression revealed significant differences between maturity stages and between sexes. Females demonstrated steeper length-to-weight regression slopes than males in the peak-breeding seasons. Aspects of squid biology pertinent to fishery management were highlighted as well as potential areas where research should be directed in order to develop future stock assessment models.
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Fernández, Álvarez Fernando Ángel. "An onto-phylogenetic journey through the life history of flying squids (Cephalopoda: Ommastrephidae)." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/606428.
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Flying squids develop all its life cycle in the water column, as planktonic paralarvae and then as nektonic subadults and adults. In this Ph. D. Thesis, light was shed over several poorly understood aspects of the ontogeny and phylogeny of the Family Ommastrephidae. The mechanism of sperm migration from spermatangia to the female seminal receptacles was studied. Spermatozoa are able to actively migrate between both structures. The morphology of the hatchling of three Mediterranean ommastrephid species was studied based on embryos obtained by in vitro fertilization and a dichotomous key was develop to identify NE Atlantic species. The first feeding diet of paralarvae was assessed through laser-capture microdissection and DNA metabarcoding. The results indicate an ontogenetic shift from detritivorism to active predation. Molecular data indicate that the taxonomic name Ommastrephes bartramii actually hides four biological species. These advances in scientific knowledge have potential applications for a better understanding of the ecology, physiology, biodiversity and fishery science that will foster a deeper understanding of flying squids.Las potas desarrollan todo su ciclo vital en la columna de agua, como paralarvas planctónicas y luego como subadultos y adultos nectónicos. En esta Tesis Doctoral, se ha arrojado luz sobre algunos aspectos poco estudiados de la ontogenia y la filogenia de Familia Ommastrephidae. Se estudió el mecanismo de migración espermática desde los espermatangios hasta los receptáculos seminales de la hembra. Los espermatozoides son capaces de migrar activamente entre ambas estructuras. Se estudió la morfología de los recién nacidos de tres especies mediterráneas de pota basándose en embriones generados por fecundación in vitro y se desarrolló una clave dicotómica para identificar las especies del Atlántico NE. Se estudió la primera alimentación de las paralarvas mediante una combinación de microdisección láser y DNA metabarcoding: los resultados indican una fase detritívora seguida de un cambio ontogenético hacia la depredación activa. Nuestros datos moleculares muestran que bajo el nombre taxonómico Ommastrephes bartramii en realidad se esconden cuatro especies biológicas. Estos avances en el conocimiento científico tienen aplicaciones potenciales para una mejor comprensión de la ecología, fisiología, biodiversidad y ciencia pesquera de las potas
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Nagel, Joachim [Verfasser], and Dieter [Akademischer Betreuer] Koelle. "Asymmetrische SQUIDs und nanoSQUIDs : Quanteninterferometer unter neuartigen Bedingungen / Joachim Nagel ; Betreuer: Dieter Koelle." Tübingen : Universitätsbibliothek Tübingen, 2012. http://d-nb.info/1162843330/34.
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Hancke, Lisa. "Dynamics of the Tsitsikamma current, with implications for larval transportof chokka squid (Loligo reynaudii) on the eastern Agulhas Bank." Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/2035.
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Thesis (MTech (Oceanography))Cape Peninsula University of Technology, 2010The current dynamics along the Tsitsikamma coast is described from a combination of acoustic current measurements. satellite-tracked surface drifters and underwater temperature recordings made between November 2006 and March 2008. The Tsitsikamma coast is largely a Marine Protected Area (MPA) that protects a rich marine biodiversity. The nearshore currents are important in the dispersal of eggs and larvae of many marine species. including the paralarvae of the commercially caught chokka squid. LoNgo reynaudii. Changes in the environment, including the currents. can affect the successful recruitment of chokka squid, and can bring about large annual fluctuations in biomass that creates economic uncertainty in the squid fishery. Results confirm the existence of a predominantly alongshore current off the Tsitsikamma coast. At Middelbank eastward flow was slightly dominant, with a percentage occurrence of 58% vs. 41% westward flow near the surface. The percentage eastward flow decreased with depth, with 41% vs. 58% westward flow near the seabed. At Thyspunt westward and eastward flow occurred at near equal percentages. but westward flow was slightly dominant throughout the water column. The alongshore current was strongest near the surface during eastward flow (maximum = 141 crn.s1: average = 27 crn.s '). while westward surface currents were weaker (maximum velocity = 78 cm.s1: average = 19 crn.s1). Current speed generally decreased with depth and opposing surface and bottom currents, associated with a thermal stratified water column, were occasionally recorded. The nearshore flow regime was characterised by frequent barotropic alongshore reversals that occurred year round. An increase in strong eastward episodes, and opposing surface and bottom currents during spring and summer months have implications for the dispersal of squid paralarvae during the summer and winter spawning seasons. In summer, the combination of strong eastward pulses in the current and upwelling at the capes favoured dispersal onto the midshelf of the Agulhas Bank. In winter, alongshore oscillations without the offshore displacement associated with upwelling. restricted offshore dispersal which caused surface particles to be retained inshore. Drifter trajectories show that both the eastward and westward nearshore current can link the inshore spawning grounds with the nursery grounds, offshore on the central Agulhas Bank; and that passive, neutrally buoyant material in the surface layer can reach the vicinity of the cold ridge in as little as eight days. The wind-driven processes of upwelling and coastal trapped waves (CTWs). and the influence of the greater shelf circulation are discussed as possible driving forces of variability in the currents off the Tsitsikamma coast. The occurrence of coastal trapped waves during thermal stratification appears to drive the jet-like, eastward pulses in the current. and results suggest that the propagation of CTWs may regulate and even enhance upwelling and downwelling along the Tsitsikamma coast.
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Keil, Stefan. "Flussquantenabbildung und lokale Analyse von niederfrequentem Flussrauschen in YBa2Cu3O7-d [YBa2Cu3O7-Delta] dc SQUIDs." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=963170228.
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Hutson, D. "The design, construction and operation of practical thin film superconducting quantum interference devices (SQUIDs)." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382345.
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McKinnon, Jean Fiona, and n/a. "Aspects of the population biology of the southern arrow squid, Nototodarus sloanii, in southern New Zealand." University of Otago. Department of Marine Science, 2007. http://adt.otago.ac.nz./public/adt-NZDU20071204.161531.
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Nototodarus sloanii is an important component of the Southern Ocean fauna, and the basis of a large commercial fishery. Despite this, much is unknown about the biology of this species. This study examines some aspects of the biology of N. sloanii.
Stomach contents analysis identified no significant differences in diet between male and female squid. Sixteen putative species, including 12 identifiable teleosts, 2 crustaceans, and 2 cephalopods were identified in the diet of this species. The euphausid, Nyctiphanes australis was the most important prey item, Lanternfish, Lampanyctodes hectoris, and Pearlside, Maurolicus muelleri, were of secondary importance.
Squid were aged using counts of statolith micro-increments and back-calculation from the date of capture showed that hatching occurred between August and February, with a peak in the austral winter/spring and another smaller peak in the austral summer. Growth rate for male squid differed depending on whether squid were hatched in the winter/spring or summer. Growth rates were more variable in the winter/spring-hatched individuals, and they attained larger size than summer-hatched squid. This was not the case for female squid. Mean age for immature winter/spring-hatched squid was significantly higher than for summer-hatched squid, although there was no significant difference in mean mantle length or body mass. No significant differences between mean age, mantle length, or body mass for same-gender mature squid, regardless of hatch season, were apparent. However, mature female squid hatched in the winter/spring season were significantly longer (ML) than mature male squid hatched in winter/spring. No squid was found to be older than 211 days. All squid had started to mature by 91-120 days old and all were fully mature at 180 days.
Validation experiments run on juvenile squid using calcein markers were inconclusive, however the increments in the statoliths were very similar to those found in other validated species of ommastrephid squid, thus for the purposes of this study they were assumed to be of daily periodicity.
Gladius increments identify a gender difference in growth rate, with female squid having a shorter initial slow growth phase than male squid.
Gonadosomatic indices (GSIs) were calculated for male and female squid. These were low (7.12%�0.3% for females and 1.9%�0.2% for males) suggesting that these squid are intermittent spawners. This is further supported by a histological examination, which found germinal cells of different stages present in the same gonad. Lack of mature individuals in this study means that these results are suggestive rather than definitive; more examination of the reproductive process of this squid is required. Histological examination was also used to validate the Lipinski maturity scale for use with this species, while some misidentification occurred the scale is useful to place squid into the broad categories of immature, maturing, or mature. New maturity scales were created for N. sloanii utilising these broad categories. Finer-scale identification is not possible using this scale, as maturation appears to be a continuous process.
Morphometric measurements were taken from both hard and soft tissues and were analysed using non-metric multidimensional scaling and analysis of similarity. Divisions were only apparent in the hard structure measurements. They did not appear to be age, dietary or reproductive differences.
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Martin, Lindsay. "Fisheries management, fishing rights and redistribution within the commercial chokka squid fishery of South Africa." Thesis, Rhodes University, 2005. http://hdl.handle.net/10962/d1007500.
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The objective of this thesis is to analyse the management and redistribution policies implemented in the South African squid industry. This is done within the broader context of fisheries policies that have been implemented within the South African fishing industry as the squid industry has developed. The study therefore has an institutional basis, which reviews the development of institutional mechanisms as they have evolved to deal fisheries management problems. These mechanisms (which can either be formal or informal) consist of committees, laws and constitutions that have developed as society has progressed. Probably the most prominent of these, in terms of current fisheries policy, is the Marine Living Resources Act (MLRA) of 1998. The broad policy prescription of the MLRA basically advocates the sustainable utilisation of marine resources while outlining the need to restructure the fishing industry to address historical imbalances and to achieve equity. It is this broad objective that this thesis applies to the squid fishery. The primary means of achieving the above objective, within the squid industry, has been through the reallocation of permit rights. These rights also provide the primary means by which effort is managed. A disruption in the rights allocation process therefore has implications for resource management as well. Permits rights can be described as a form of use right or propertY right. These rights are structured according to their operational-level characteristics, or rules. Changing these rules can thus affect the efficiency or flexibility of a rights based system. This is important because initial reallocation of rights, by the Department of Environmental Affairs and Tourism (DEAT), was based on an incomplete set of rights. This partly led to the failure of early redistribution attempts resulting in a "paper permit" market. Nevertheless, this thesis argues that redistribution attempts were based on ill-defined criteria that contributed to the failure described above. In addition to this the method through which redistribution was attempted is also questionable. This can be described as a weak redistribution strategy that did not account for all equity criteria (i.e. factors like capital ownership, employment or relative income levels). This thesis thus recommends, among other things, that an incentive based rights system be adopted and that the design of this system correctly caters of the operational-level rules mentioned above. In addition to this a strong redistribution, based on fishing capital, ownership, income and the transfer of skills, should be implemented.KMBT_363
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Coupiac, Olivier. "Réalisation d'un dispositif à 3 SQUIDs pour la mesure de corrélations de bruit de grenaille." Phd thesis, Grenoble 1, 2007. http://www.theses.fr/2007GRE10157.
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Ce projet de these est consacre a la construction et l'optimisation d'un dispositif de mesure de corrélations de bruit en courant à très basse température. Au cours des deux dernières décennies, le bruit de grenaille s'est révélé être un outil puissant d'investigation des propriétés de transport électronique des conducteurs mésoscopiques. En particulier, dans le cas de nanostructures à trois terminaux, la mesure des corrélations du bruit de grenaille entre deux terminaux permet de sonder la statistique des porteurs et leurs interactions. Dans le cas où les interactions peuvent être négligées, des particules obéissant à une statistique bosonique conduisent à des corrélations positives. Pour une statistique fermionique, les corrélations seront au contraire négatives. Ces résultats ont été confirmés expérimentalement à plusieurs reprises pour les deux familles de particules, notamment grâce aux expériences fondatrices menées au cours des années 1950 par hanbury-brown et twiss sur des photons provenant d'une étoile. En revanche, lorsqu'un supraconducteur est connecté à deux bras de métal normal (n/sin), l'interaction bcs peut induire des corrélations positives dans ce système fermionique par le biais de la réflexion d'andreev qui transforme une paire de cooper en deux électrons dans les bras normaux. La mesure de ces corrélations doit permettre la mise en évidence expérimentale du caractère non local de la réflexion d'andreev, ainsi que de l'existence d'états intriqués à deux particules. L'objectif du dispositif construit est de mesurer de telles corrélations. Le présent manuscrit décrit les étapes du projet, du travail de mise au point de l'instrument et de fabrication des échantillons jusqu'aux mesures préliminairesIN THIS PH-D THESIS WE HAVE DEVELOPPED A SET-UP TO MEASURE CURRENT NOISE CORRELATIONS AT VERY LOW TEMPERATURE. OVER THE PAST TWO DECADES, SHOT NOISE HAS BEEN WIDEL Y USED TO INVESTIGATE ELECTRONIC PROPERTlES OF MESOSCOPIC DEVICES. IN THE PARTICULAR CASE OF THREE-TERMINAL NANOSTRUCTURES, SHOT NOISE CORRELATIONS BETWEEN TWO TERMINALS ARE SENSITIVE TO THE STATISTICS OF PARTICLES AND THEIR INTERACTIONS. WHEN INTERACTIONS CAN BE NEGLECTED, CORRELATIONS ARE POSITIVE FOR BOSONS AND NEGATIVE FOR FERMIONS. THIS HAS BEEN CONFIRMED EXPERIMENTAL Y FOR DIFFERENT KIND OF PARTICLES AND FOR BOTH ST A TISTICS, NAMEL Y WITH HISTORICAL EXPERIMENT BY HANBURY-BROWN AND TWISS ON PHOTONS. YET, IN HYBRID NORMAL-SUPERCONDUCTOR DEVICE, THINGS CAN BE DIFFERENT. FOR A SUPERCONDUCTOR CONNECTED TO TWO NORMAL METAL TERMINALS, ANDREEV REFLECTION TRANSFORMS A COOPER PAIR IN TWO ELECTRONS IN NORMAL METAL TERMINALS, AND BCS INTERACTION CAN INDUCE POSITIVE CORRELATIONS. MEASURING CORRELATIONS CAN BE USED TO PROBE NON LOCAL PROPERTIES SUCH AS CROSSED ANDREEV REFLECTION, OR ENTANGLEMENT OF THE ANDREEV PAIR. THE SET-UP DESCRIBED HERE AIMS AT MEASURING SUCH CORRELATIONS. THE THESIS MANUSCRIPT DESCRIBES THE DIFFERENT STEPS OF THE PROJECT, FROM INSTRUMENTATION AND SAMPLE PRODUCTION TO PRELIMINARY MEASUREMENTS
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Coupiac, Olivier. "Réalisation d'un dispositif à 3 SQUIDs pour la mesure de corrélations de bruit de grenaille." Phd thesis, Université Joseph Fourier (Grenoble), 2007. http://tel.archives-ouvertes.fr/tel-00290007.
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Ouanani, Saphia. "Étude de réseaux de jonctions Josephson à haute température critique." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS208.
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La jonction Josephson (JJ) est le composé de base de nombreux circuits électroniques supraconducteurs (SQUID, détecteurs d’ondes millimétriques, logique RSFQ). Avec la découverte des supraconducteurs HTc (à haute température critique), d’intenses recherches ont été entreprises pour réaliser des JJ fonctionnant à la température de l’azote liquide (77 K) permettant l’utilisation d’une cryogénie compacte. Toutefois, la complexité de ces matériaux a longtemps rendu difficile le développement d’une technologie viable et simple à mettre en œuvre. Parmi les méthodes de fabrication de jonctions, celle utilisant l’irradiation par faisceau d’ions a atteint un niveau de maturité suffisamment important pour pouvoir envisager la production de circuits comportant plusieurs milliers de JJ à HTc.Le but de ma thèse repose sur la fabrication, la caractérisation et l’étude des propriétés électromagnétiques de réseaux de jonctions Josephson réalisés dans des films minces d’YBa2Cu3O7-d. par la méthode d’irradiation ioniqueThe Josephson junction (JJ) is the basis of many compound superconducting electronic circuits (SQUID detectors millimeter wave RSFQ logic). With the discovery of HTS superconductors (high critical temperature), intensive research has been undertaken to make JJ operating at the temperature of liquid nitrogen (77 K) allowing the use of a compact cryogenics. However, the complexity of these materials has long hampered the development of a viable technology and simple to implement. Among the junctions manufacturing methods, one using the ion beam irradiation has reached a sufficiently high degree of maturity to be able to envisage the production of circuits having thousands of JJ to HTS.The aim of my thesis is based on the fabrication, characterization and study of the electromagnetic properties of Josephson arrays achieved in thin films of YBa2Cu3O7-d. by the ion irradiation method
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Moura, Matheus Sacilotto de. "Desenvolvimento em um biogradiômetro multicanal supercondutor com SQUIDs DC para registro de medidas de magnetocardiografia fetal." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/59/59135/tde-04042012-141710/.
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Neste projeto trabalhou-se no desenvolvimento de uma nova instrumentação para registrar medidas de campos magnéticos de origem biológica baseados em sensores SQUID e sistemas auxiliares, com o objetivo de usar este arranjo na aquisição de medidas de magnetocardiografia fetal (MCGf), que consiste no registro dos campos magnéticos gerados pela atividade cardíaca fetal, refletindo seus processos eletrofisiológicos. Esta técnica biomagnética além de ser bastante precisa para obter medidas de campo magnético originado do coração fetal, que é da ordem de dez picoteslas a poucos centímetros de distância do abdômen materno, também realiza medidas de forma não-invasiva, o que a torna bastante promissora. Contudo, não se conseguiu a sensibilidade desejada do sistema biogradiométrico, sendo alcançada uma sensibilidade capaz de detectar o sinal magneto-cardiográfico (MCG) de um sistema cardíaco desenvolvido, que é da ordem de 100 pT. Neste trabalho reuniu-se, ainda, toda a informação obtida pelo grupo de biomagnetismo no decorrer dos últimos anos referente ao sistema biogradiométrico multicanal.In this project we worked in the developing of a new instrumentation for mea- sure magnetic fields of biological source based in SQUID sensors and auxiliares systems, with aim of use this suite in measures of fetal magnetocardiography (fMCG), that is the recording of the magnetic fields generated by the fetal heart's activity, reflecting the electrophysiological processes that happen in it. This biomagnetic technique besides to be accurate enough to obtain measures of the magnetic field originated from the fetal heart, that is of the order of ten picoteslas at a few centimeters distance from the maternal abdomen, also realizes measures in outside sections at the mother's body turning it so promise. However, not obtained the desired sensitivity of the biogradiometer system, achieving just a sensitivity capable of detecting the magnetocardiography (MCG) signal of a developed cardiac system, which is about 100 pT. This work has met, yet, all information obtained by the biomagnetism group over the past years referent to the multichannel biogradiometer system.
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Back, Christoph. "UHV-Cluster-Anlage zur Herstellung von Dünnfilmstrukturen und Transport- und Rauscheigenschaften von YBa2Cu3O7-d-Korngrenzen-SQUIDs." [S.l. : s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=984577629.
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Wong, Ying-yee, and 黃影怡. "The squid jigging industry in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45013640.
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Ridereau, Xavier. "Étude théorique et expérimentale du piégeage de vortex dans des couches minces supraconductrices à haute température critique : application à l'optimisation, dans le domaine des basses fréquences, de microcapteurs magnétiques supraconducteurs." Caen, 2003. http://www.theses.fr/2003CAEN2004.
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Le bruit excédentaire dans les capteurs magnétiques supraconducteurs à haute température critique est un problème important vis à vis des applications visées en magnétométrie. Des études ont notamment montré que certains choix technologiques (diminution du concentrateur, amélioration de la qualité de la couche, écluses de flux,. . . ) permettaient de diminuer le bruit de vortex. Pour poursuivre ces études, nous avons réalisé une canne de mesure magnétiquement blindée plongeant dans l'hélium liquide et munie d'un étage à température variable. Un système de mesure complet permettant l'étude simultanée de deux magnétomètres de type SQUIDs couplés au même concentrateur de flux a été réalisé. L'influence des vortex piégés (champ d'offset, bruit) dans les magnétomètres supraconducteurs a été étudiée en fonction du champ appliqué à la transition ou après la transition supraconductrice. Ces expériences ont montré l’importance des vortex proches de la boucle du SQUID.
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Bailer, Matthias [Verfasser], and Dieter [Akademischer Betreuer] Kölle. "Abbildung, Manipulation und Flussrauschen einzelner Abrikosov-Vortices in YBa2Cu3O7-delta dc SQUIDs / Matthias Bailer ; Betreuer: Dieter Kölle." Tübingen : Universitätsbibliothek Tübingen, 2013. http://d-nb.info/1162897066/34.
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Keil, Stefan. "Flußquantenabbildung und lokale Analyse von niederfrequentem Flußrauschen in YBa 2 Cu 3 O 7 -delta dc SQUIDs." [S.l. : s.n.], 2000. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB8849727.
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Cyrille, Marie-Claire. "Étude et réalisation de SQUIDS à polarisation continue pour l'amplification radiofréquence à très faible température de bruit." Université Joseph Fourier (Grenoble ; 1971-2015), 1996. http://www.theses.fr/1996GRE10228.
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Le squid dc (superconducting quantum device direct current) est un capteur de flux extremement sensible. Associe a un circuit de couplage approprie, il est bien adapte pour l'amplification de tres faibles signaux dans la gamme de frequence 1-150mhz. Ce travail presente l'etude de l'optimisation de l'ensemble des parametres geometriques et electriques des amplificateurs a squid ; la mise en place des procedes technologiques necessaire a leur fabrication ainsi que la mesure de leurs performances. La fabrication de jonctions josephson nb/al-alox/nb de petite surface ( 4m#2), elements de base des squids a ete etudiee puis optimisee avec une bonne reproductibilite de leurs parametres electriques. Une premiere approche du probleme a consiste a realiser et caracteriser des squids en niobium non couples. Enfin, la geometrie des squids et de leurs structures de couplage est choisie avec un large choix de parametres qui permettra ulterieurement de definir ceux les mieux adaptes a l'amplification. Un procede technologique multi-couches complet est alors defini puis etudie pour la realisation des dispositifs. Leur caracterisation electrique met en evidence la modification du fonctionnement des squids en presence de leur structure de couplage
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Borca, Bogdana. "Etude de la croissance et des propriétés magnétiques de systèmes auto-organisés de nanofils de Fer(110)." Phd thesis, Université Joseph Fourier (Grenoble), 2007. http://tel.archives-ouvertes.fr/tel-00130572.
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Le sujet de thèse concerne l'étude de réseaux réguliers de nanofils magnétiques auto-organisés. Deux approches ont été utilisées pour la fabrication : 1) Préparation de réseaux planaires de nanofils alternés (Fe,Ag) sur Mo(110). Ce mode de croissance est attribué au caractère non miscible des deux métaux et à un mécanisme modulé de relaxation des contraintes d'épitaxie. 2) Préparation de nanofils de Fer sur une surface déjà structurée en tranchées périodiques. Ces tranchées se forment spontanément lors de la croissance homoépitaxiale d'un métal cc de W(110) (ou Mo) à température modérée. La période de la structuration unidimensionnelle est contrôlable par la température de dépôt. La deuxième étape consiste à déposer le Fer sur ce gabarit. Pour une température définie, Fe croît au fond des tranchées pour former des fils régulièrement espacés. Des réseaux de fils en trois dimensions ont aussi été fabriqués. Du point de vue magnétique, les deux systèmes présentent une forte anisotropie uniaxiale avec l'axe de facile aimantation planaire, le long des fils. A température ambiante les systèmes sont superparamagnétiques. L'évolution de la coercitivité en fonction de la température s'interprète selon un processus de renversement d'aimantation thermiquement activé par nucléation/propagation. Le renversement met en jeu plusieurs fils couplés pour le premier système et s'effectue au sein des fils individuels dans le deuxième.
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Aboussouan, Pierre. "Interférences à deux photons à 1550 nm pour les communications quantiques." Nice, 2008. http://www.theses.fr/2008NICE4087.
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Cette thèse présente l’étude et la réalisation d’une expérience d’interférence à deux photons de type Hong-Ou-Mandel appelé aussi coalescence des photons. L’originalité de notre travail réside dans l’utilisation de deux sources de photons uniques annoncées indépendantes dont le fonctionnement requiert l’utilisation de guides d’ondes intégrés sur un substrat de niobate de lithium polarisé périodiquement (PPLN). Les photons acteurs de l’interférence sont créés par génération paramétrique à la longueur d’onde de 1550 nm nous assurant ainsi une compatibilité avec le réseau des fibres optiques télécom. Les guides PPLN présentent l’avantage majeur d’avoir une forte efficacité de conversion, mais ils permettent également de récolter aisément les photons à l’aide d’une fibre optique. Le travail effectué nous a conduit à étudier le comportement des guides dans différents régimes de fonctionnement : continu et impulsionnel. En effet, comparativement aux expériences de coalescence réalisés part le passé, nous avons choisi de travailler en régime picoseconde afin de faciliter l’obtention de l’interférence en regard de la synchronisation électronique et du filtrage a effectué. Les visibilités obtenus (99%) sont proches des limites théoriques et ces résultats montrent que le protocole expérimental mis en place peut devenir l’un des éléments clés des futurs protocoles des communications quantiques utilisant les phénomènes de coalescenceThis thesis presents the study and the realisation of a Hong-Ou-Mandel two-photon interference experiment, also known as photons coalescence. The originality of our work concerned is attached to dealing with two separate sources of independent unique photons whose operative mode requires using guide beams integrated on a periodically polarised lithium niobate substratum (PPLN). The photons, actors of the interference work, are created by parametric down conversion to 1550 nm beam wavelength insuring a compatibility with the telecom optic fibres network. The PPLN guides are particularly profitable because of their very strong conversion efficiency, but they also allow easy photons harvesting through an optic fibre. The work undertaken led us to study the guide’s behaviour under different office regimes: continuous and impulsional. In fact, and in comparison to coalescence experiments formerly realised, our option was to perform in a picosecond’s regime, aiming to obtain more easily the interference in regard of the electronic synchronisation and the strain filter to be realised. The 99 % visibilities, thus obtained are very close to the theoretical limits, and these results demonstrate that the experimental procedure realised can be one of the key elements of future quantum communication protocols exploiting the coalescence phenomenon
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Trübenbach, Katja [Verfasser]. "Hypoxia tolerance of jumbo squids (Dosidicus gigas) in the Eastern Pacific oxygen minimum zones : physiological and biochemical mechanisms / Katja Trübenbach." Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/104709682X/34.
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Graham, David. "Non-destructive evaluation of damaged carbon fibre reinforced polymers using high critical temperatures SQUIDs and neural network signal processing techniques." Thesis, University of Strathclyde, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501901.
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Straub, Rainer. "Abbildung von Flussquanten in YBa 2 Cu 3O7 -x SQUIDs und Josephsonströmen in YBa 2 Cu 3O7-x-Niob Kontakten." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10873186.
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Pinker, David Stephen. "An investigation of YBCO thin-film SQUIDs with gold damping resistors and the behaviour of planar gold- c-axis YBCO contacts." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612906.
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Lam, Chok Sing Marc. "Realisation et caracterisation de squids continus a microponts sur films minces de niobium et dans des constrictions de ceramiquesupraconductrice a haute temperature critique." Caen, 1989. http://www.theses.fr/1989CAEN2002.
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Etude experimentale sur le comportement individuel des microponts en nb apres reglage par impulsions de courant et presentation des performances en bruit de fond a haute frequence et en 1/f. Des squids continus realises dans des constrictions de materiau massif d'ybacuo et de tibacacuo fonctionnant a 77 k permettent de fabriquer de facon simple des capteurs magnetiques ultrasensibles
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Barcellos, Diogo Destro. "Estatólitos da lula Doryteuthis plei e suas microestruturas para o estudo da idade e crescimento no litoral norte do Estado de São Paulo, Brasil." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-10022015-102011/.
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A idade e crescimento da lula Doryteuthis plei da região do litoral norte do Estado de São Paulo é descrita com base em 424 exemplares entre 1,58 a 267 mm de comprimento de manto (ML). Os estatólitos foram utilizados como ferramenta de análise de idade, bem como foi realizado um estudo ontogenético de sua morfometria e morfologia. Com o objetivo de analisar e aprimorar a curva e a taxa de crescimento de D. plei, o presente estudo deu ênfase aos indivíduos em estágios iniciais do ciclo de vida. O formato dos estatólitos foi descrito e demonstrou semelhança à de outros loliginídeos, porém com características particulares, suficientes para a identificação da espécie. Houve relação entre ML e o comprimento dos estatólitos (SL), obtido pelo modelo de ajuste logarítmico. A idade dos exemplares amostrados foi estimada e com isto foi possível obter a curva de crescimento (relação idade e ML) da população em estudo, a qual foi ajustada pelo modelo logístico. O mesmo modelo de ajuste houve para os machos, porém para as fêmeas e para os juvenis, o melhor modelo foi o Gompertz. A longevidade da espécie no local de estudo foi estimada em aproximadamente oito meses. A taxa de crescimento e suas variações conforme as estações do ano foram estimadas. Foram evidenciados valores sendo em mm/dia quando em estádio imaturos em relação aos adultos e decrécimo acelerado após atingir 60 mm ML. Foram observadas diferenças da taxa de crescimento entre os sexos quando os exemplares atingem 150 mm de ML. Espécimes nascidos no inverno apresentaram maiores taxas de crescimento em relação aos nascidos em outras estações do ano. Através do retro-cálculo da idade, foi observado que durante todo o ano ocorrem nascimentos de D. plei, em maior frequência no primeiro semestre. É possível estimar a idade de D. plei tendo apenas as medidas de SL ou comprimento dos domos, sendo que para cada relação, o ajuste obtido foi o logarítmico. Os parâmetros de crescimento apresentados no presente estudo oferecem recursos para estudos de avaliação do estoque pesqueiro e biologia populacional.Age and growth of the squid Doryteuthis plei from the northern shelf off São Paulo are described based on 424 specimens from 1.58 to 267 mm mantle length (ML). Statoliths were used as microstructures for aging, and an ontogenetic study of their morphological and morphometric was performed. The present study aimed to analyze and improve the growth curve and growth rate estimate of individuals of D. plei, emphasizing those in early stages of life cycle. The shape of statoliths was described and demonstrated similarity other loliginids, with particular characteristics sufficient to identify the species. There was a relationship between ML and statoliths length (SL) by the logarithmic model. The age of sampled specimens was estimated and it was possible to obtain the growth curve (relationship between age and ML) of the population in study, was better fitted by the logistic model. The same adjustment was found for males, but for females and juveniles, the Gompertz model was best suitable. The longevity of the species from place of study was estimated at approximately eight months. The growth rate and its variations were estimated according to the seasons, which evidenced higher values in mm/day in immature stage when compared to adults. In addition, individuals after reaching 60 mm ML accelerated a decrease in growth rate. Differences in growth rate between sexes were found after specimens reach 150 mm ML. Specimens born in winter had higher growth rates when compared to those born in other seasons. Through retro-calculation of age, it was observed that births of D. plei occur throughout the year, but most frequently in the first half. The study enables the age estimate of D. plei having only measures of SL or length of the statolith\'s domes. Growth parameters obtained provide information useful for stock assessment and population biology.
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Gire, Frédéric. "Caractérisation de jonctions Josephson monocouche et multicouche à haute température critique : étude du modèle de conduction et des résonances dans les jonctions Josephson réalisées sur substrat bicristallin." Caen, 1997. http://www.theses.fr/1997CAEN2083.
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Depuis l'avènement des supraconducteursà haute température critique, de nombreuses études ont été menées pour réaliser des jonctions Josephson qui constitue l'élément de base de nombreux capteurs. Ce travail est une étude expérimentale portant sur la détermination des performances des différentes technologies de jonctions Josephson monocouche et multicouche. Dans la première catégorie, nous avons étudié des jonctions réalisées à partir de films polycristallins, des jonctions sur marche, des jonctions sur substrat bicristallin SrTiO3, MgO ainsi que des nanoponts obtenus par affaiblissement de la supraconductivité par passage de faisceau d'ions focalisé (F. I. B. ). Dans l'autre catégorie, nous avons travaillé sur des jonctions tricouche réalisées YBaCuO/PrBaCuO/YBaCuO avec diverses orientations cristallines [100][110][103] et comportant une barrière soit isolante ou bien composé par un oxyde supraconducteur aux propriétés dégradées. Après avoir présenté l'électronique spécifique que nous avons développée pour mener à bien ce travail, nous présentons pour chaque type de jonction, les résultats des caractérisations des propriétés de transport, les performances sous champ magnétique mais aussi l'étude des résonances intrasèques au niveau de la barrière (Zero Field Steps et résonances de Fiske)
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AGUS, BLONDINE. "Studio sui calamari Loligo vulgaris (Lamarck, 1798) e Loligo forbesii (Steenstrup, 1856) delle acque della Sardegna." Doctoral thesis, Università degli Studi di Cagliari, 2015. http://hdl.handle.net/11584/266559.
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This thesis aims to deepening knowledge on the biology and ecology of the two squids Loligo vulgaris (Lamarck, 1798) and Loligo forbesii (Steenstrup, 1856) from Sardinian waters. Considering their socio- economic importance in the Sardinian fisheries, the annual fluctuations in abundance highlighted the possibility of set management measures for their rational exploitation on the base of the knowledge of their life cycle Even if their different preferential bathymetric range, the study of the reproductive process through macroscopic histological and gravimetric analysis of the reproductive systems showed similarities between the two squids both in morphology of the gonads and in the pattern of reproduction. They are similar because they show an extended period of sexual maturity; they have an intermittent spawning with intermediate characteristics between coastal and deep spawning. In particular specific results on the reproductive output of L.vulgaris, showed a potential fecundity of about 4000 eggs (size 0.30-3 mm) and 436 spermatophores (size 7.25-17.37 mm) according to the few studies so far carried out on the species. The reading of the age from the eye lens, tested here for the first time on cephalopods decapods, has allowed to estimate for both species a life cycle of about 18-20 months. For both squids were also performed morphometric analysis of the beaks and calculated specific correlations with the animal size. Considering the taxonomic value of the beak such information may be helpful in studies on diets of predators of these species.
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Neto, Antonio Lacerda Santos. "Modélisation prédictive des dispositifs nanoélectroniques." Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALY022.
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Galan, Elias Jason. "Magnesium Diboride Superconducting Devices and Circuits." Diss., Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/353715.
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PhysicsPh.D.
While magnesium diboride (MgB2) was first synthesized in the 1950s, MgB2’s superconductive properties were not discovered until 2001. It has the highest superconducting transition temperature of all the metallic superconductors at ~39 K at atmospheric pressure. MgB2 is also unique in that it has a two superconductive gaps, a pi gap at 2 meV and a sigma gap at 7.1 meV. There are a theoretical models discussing the inter- and intra- gap scattering of the superconductivity of MgB2 and the Josephson transport of MgB2 Josephson Junctions. The focus of this work is to further the study of all-MgB2 Josephson junctions and quantum interference device technology. This work discusses the transport in all-MgB2 Josephson junctions and designing, fabricating, and measuring multi-junction devices. The junctions studied include all-MgB2 sandwich-type Josephson junctions (one with TiB2 normal conducting barrier and another with an MgO insulating barrier). The junction MgB2 films were deposited by hyprid physical-vapor deposition and the junction barrier were deposited by sputtering. The junctions were patterned and etched with UV photolithography and argon ion milling. With the TiB2 barrier we studied Josephson transport by the proximity effect. With these junctions, we also observed complete suppression of the critical current by an applied magnetic field showing for the first time a leakage free barrier in an all-MgB2 Josephson junction with a single ultrathin barrier. We also studied junctions utilizing MgO barrier deposited by reactive sputtering which gave a larger characteristic voltage of 1-3 mV compared to TiB2 barriers. By connecting several SQUIDs with varying loop areas we developed of two types of superconducting quantum interference filters (SQIFs). The first SQIF designed with 21 SQUIDs connected in parallel and the SQUID loops are sensitive to magnetic fields applied parallel to the substrate. The SQUID loop areas were designed to vary in such a way that the voltage modulation gave a unique peak corresponding to the absolute value of the applied magnetic field. The SQIF shows an antipeak height of 0.25 mV with a transfer function of 16 V/T at 3 K. The lowest noise measured for this SQIF is 110 pT/Hz1/2. The second SQIF is designed with 17 SQUIDs in parallel and the SQUID loops are sensitive to magnetic field perpendicular to the substrate. This SQIF has shown improved voltage modulation with a peak height of 1 mV and a transfer function of 7800 V/T. The noise sensitivity was measured at 70 pT/Hz1/2. The sensitivity of the SQIF shows MgB2 potential superconductor to improve performance of current superconductive electronics. Utilizing known all-MgB2 junctions and SQUID parameters two rapid single flux quantum (RSFQ) circuits were designed and tested. A toggle flip flop (TFF) operating as a frequency divider was developed. The TFF design consisted of a Josephson transmission line, a splitter, and an interferometer (a DC SQUID). The TFF utilized an improved designed, compared to previous all-MgB2 TFFs, and showed operation up to 335 GHz at 7 K and operation up to 30 K. A low frequency set-reset flip flop (SRFF) was also developed to demonstrate RSFQ digital logic. The SRFF design includes a DC-SFQ converter, a Josephson transmission line, and an inductively coupled readout SQUID. The SRFF demonstrates proper digital logic by toggling between a high and low voltage state with a sequential set and reset input. While these developed devices are not close to the potential that MgB2 allows, they do show the promise MgB2 based devices have in making more sensitive and faster superconductive logic devices.
Temple University--Theses