Dissertations / Theses on the topic 'Spin'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Spin.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Serral, Gracià Rubèn. "Spin bosons and spin glasses." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2004. http://dare.uva.nl/document/76076.
Full textPerumal, Sathya Sai Ramakrishna Raj. "Spin-Orbit and Spin-Spin Coupling in the Triplet State." Doctoral thesis, KTH, Teoretisk kemi och biologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-95761.
Full textQC 20120531
Perumal, Sathya S. R. R. "Spin-Spin and Spin-Orbit couplingstudies of small species andmagnetic system." Licentiate thesis, KTH, Theoretical Chemistry, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12353.
Full textThe spin of an electron often misleadingly interpreted as the classical rotationof a particle. The quantum spin distinguishes itself from classicalrotation by possessing quantized states and can be detected by its magneticmoment. The properties of spin and its collective behavior with otherfundamental properties are fascinating in basic sciences. In many aspectsit offers scope for designing new materials by manipulating the ensemblesof spin. In recent years attention towards high density storage devices hasdriven the attention to the fundamental level were quantum physics rules.To understand better design of molecule based storage materials, studies onspin degrees of freedom and their coupling properties can not be neglected.
To account for many body effect of two or more electrons consistent withrelativity, an approximation like the Breit Hamiltonian(BH) is used in modernquantum chemical calculations, which is successful in explaining the splitin the spectra and corresponding properties associated with it. Often differenttactics are involved for a specific level of computations. For example themulti-configurational practice is different from the functional based calculations,and it depends on the size of the system to choose between resourcesand accuracy. As the coupling terms offers extra burden of calculating theintegrals it is literally challenging.
One can readily employ approximations as it suits best for the applicationoriented device computations. The possible methods available in the literatureare presented in chapter 2. The theoretical implementations of couplingfor the multi-reference and density functional method are discussed in detail.The multi-reference method precedes the density functional methodin terms of accuracy and generalizations, however it is inefficient in dealingvery large systems involving many transition elements, which is vital formolecule based magnets as they often possess open shell manifolds. On theother hand existing density functional method exercise perturbations techniqueswhich is extremely specialized for a specific system - highly coupledspins.
The importance of spin-spin coupling(SSC) in organic radical-Oxyallyl(OXA)was systematically studied with different basis sets and compared with asimilar isoelectronic radical(TMM). The method of spin-spin coupling implementationsare also emphasized. Similar coupling studies were carriedivout for the species HCP and NCN along with spin-orbit coupling(SOC).The splitting of the triplet states are in good agreement with experiments
Mooser, Sebastian Thomas. "Spin injection, spin transport and spin-charge conversion in organic semiconductors." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608211.
Full textBatley, Joseph Thomas. "Spin transport in lateral spin valves." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/12176/.
Full textLin, Ran. "Organic spintronic devices utilizing spin-injection, spin-tunneling and spin-dependent transport." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/5015.
Full textPerumal, Sathya S. R. R. "Spin-Spin and Spin-Orbit coupling studies of small species and magnetic system." Licentiate thesis, KTH, Teoretisk kemi (stängd 20110512), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12353.
Full textQC 20110210
Sodickson, Daniel Kevin. "Spin-spin couplings in two limits : experimental, theoretical, and computational studies of dipole-coupled nuclear spins in solids." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/32601.
Full textIncludes bibliographical references (leaves 193-200).
by Daniel Kevin Sodickson.
Ph.D.
Rodríguez-Arias, Inés. "Collective behaviours in interacting spin systems." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS332/document.
Full textDynamic nuclear polarization (DNP) is one of the most promising techniques towards a new generation of Magnetic Resonance Imaging (MRI). The idea is to use the Nuclear Magnetic Resonance (NMR) in other nuclei rather than the traditional hydrogen, such as carbon. For the carbon signal to be detected, one needs to enhance its spin polarization. In thermal equilibrium — at low temperature and high magnetic field — electron spins are far more polarized than any system of nuclear spins, which is due to their smaller mass. With the DNP technique we bring the system out-of-equilibrium irradiating it with microwaves. This triggers polarization transfer from the electron spins to the nuclear ones. During my Ph.D, I have studied both analytically and numerically the competition between the dipolar interactions among electron spins (which can be tuned experimentally) and the disorder naturally present in the sample. I proposed two models to study DNP: a Heisenberg spin-chain and a system free-fermions in the Anderson model. Two different regimes were found : For strongly interacting electron spins, the out-of-equilibrium steady state displays an effective thermodynamic behavior characterised by a very low spin temperature. In the weakly interacting regime, it is not possible to define a spin temperature, and it is associated to a many-body localized phase (or an Anderson-localized phase). My research was focused on the properties of the two phases with respect to the performance of DNP, and I found it to be optimal at the transition between the two. This is a very important result that has been verified by recent experiments carried in École Normale Supérieure de Paris
Konovalenko, Alexander. "Spin transfer torques and spin dynamics in point contacts and spin-flop tunnel junctions." Doctoral thesis, Stockholm : Department of Physics, Royal Institute of Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4805.
Full textEvers, Martin [Verfasser]. "Two antagonizing aspects of spin transport : spin-wave localization and spin superfluidity / Martin Evers." Konstanz : KOPS Universität Konstanz, 2019. http://d-nb.info/1230323309/34.
Full textNotbohm, Susanne. "Spin dynamics of quantum spin-ladders and chains." Thesis, St Andrews, 2007. http://hdl.handle.net/10023/403.
Full textWoo, Seonghoon. "Manipulation of spin textures by unconventional spin torques." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98577.
Full textThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references.
Dynamically controlling magnetism at the nanoscale is the foundation for realizing high-performance, low-power solid-state spintronic devices. The manipulation of nonuniform magnetization textures such as domain walls and skyrmions provide both a means to control magnetism in devices, and to gain new fundamental insights into spin-charge and spin-orbital interactions in magnetic materials. In this thesis, we examine novel mechanisms for the evolution and control of nonuniform magnetization textures. We first show that magnonic spin currents due to spin wave propagation can couple to and drive magnetic domain walls in nanowires mainly with experiments, supported by micromagnetic simulations. This work highlights a route towards integrating domain walls and spin waves for enhanced functionality in spintronics applications. We then focus on pure spin currents generated at the interface between a metallic ferromagnet and a heavy metal due to the spin Hall effect induced by strong spin orbit interaction. We demonstrate that the spin Hall effect can efficiently amplify or attenuate spin waves in an adjacent ferromagnet, and the efficiency of spin current generation can also be dramatically enhanced by optimizing the ferromagnet/heavy-metal interfaces. Moreover, we describe the microscopic mechanisms by which the spin Hall effect leads to magnetization switching, in the presence of chiral exchange interactions due to interfacial Dzyaloshinskii-Moriya interaction. This work shows the essential role that Dzyaloshinskii-Moriya interaction plays in magnetization switching. Finally, by harnessing this effect in carefully engineered materials, we show for the first time that the Dzyaloshinskii-Moriya interaction can stabilize topologically-protected skyrmions, whose statics and dynamics we have imaged for the first time in transition-metal ferromagnets at room temperature without any static external bias field. This finding provides not only experimental evidence of recent predictions but also opens the door to room-temperature skyrmion spintronics in robust thin-film heterostructures
by Seonghoon Woo.
Ph. D.
Qureshi, Tariq. "Spin chemistry." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365292.
Full textJackson, Stephen Siegel Robert. "Spin Cycle." [Greenville, N.C.] : East Carolina University, 2009. http://hdl.handle.net/10342/2236.
Full textKalappattil, Vijaysankar. "Spin Seebeck effect and related phenomena in functional magnetic oxides." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7632.
Full textBelkhir, Mohamed Akli. "Structure de bandes à spin polarisé par la méthode des fonctions localisées : application à MnO et NiO." Metz, 1988. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1988/Belkhir.Mohamed_Akli.SMZ8812.pdf.
Full textA spin polarized band calculation based on a localized function method has been performed on MnO and NiO in their antiferromagnetic configuration. When the intra-atomic exchange is strong enough like in MnO, a gap appears between the majority and minority d bands which suffices to explain the insulating behaviour of that oxide. Further it has been show that a gap is systematically opened in each majority and minority band due in NiO is responsible for its semiconducting properties. Thus the p-d hybridization which prevents the gap formation in the NaCl structure leads to a satisfactory issue only when the magnetic ordering is taken into account
Garzon, Samir Y. "Spin injection and detection in copper spin valve structures." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2192.
Full textThesis research directed by: Physics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Graf, Tobias. "Spin-spin interactions of localized electronic states in semiconductors." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970274157.
Full textLi, Jian. "Spin transport in mesoscopic systems with spin-orbit coupling." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B39794015.
Full textKamenskyi, Dmytro. "Electron spin resonance studies of frustrated quantum spin systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-108777.
Full textLeontiadou, Marina A. "Spin dynamics and spin control in narrow gap semiconductors." Thesis, University of Surrey, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580626.
Full textCharnock, Gareth Trevor Patrick. "Computational spin dynamics and visualisation of large spin systems." Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.601126.
Full textLi, Jian, and 李牮. "Spin transport in mesoscopic systems with spin-orbit coupling." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39794015.
Full textChild, Abigail. "Spin diffusion and spin rotation in '3He-'4He solutions." Thesis, University of Nottingham, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357967.
Full textSteinmüller, Stephan Jan. "Optical studies of electron spin transport and spin dynamics." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616269.
Full textPatrakov, Alexander. "Topologische Analysen von NMR-Spin-Spin-Kopplungspfaden über Realraumfunktionen." kostenfrei, 2008. http://www.opus-bayern.de/uni-wuerzburg/volltexte/2008/2850/.
Full textGöpfert, Alois. "Classical description of dynamical many-body systems with central forces, spin-orbit forces and spin-spin forces." Bordeaux 1, 1994. http://www.theses.fr/1994BOR10551.
Full textRecher, Patrik. "Correlated spin transport in nanostructures: entanglement creation and spin filtering." Basel : Universität Basel, 2003. http://www.unibas.ch/diss/2003/DissB_6688.htm.
Full textBühler, Alexander. "High temperature series expansions for spin and spin phonon systems." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969818203.
Full textArango, Yulieth Cristina. "Electron spin resonance (ESR) spectroscopy of low-dimensional spin systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-69811.
Full textOzerov, Mykhaylo. "High-field electron spin resonance in low-dimensional spin systems." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-69892.
Full textChang, Ming-Shien. "Coherent Spin Dynamics of a Spin-1 Bose-Einstein Condensate." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10547.
Full textMohseni, Armaki Seyed Majid. "Spin valves and spin-torque oscillators with perpendicualr magnetic anisotropy." Doctoral thesis, KTH, Materialfysik, MF, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105223.
Full textQC 20121119
Rhensius, Jan [Verfasser]. "Spin Dynamics and Spin Configuration in Nanopatterned Elements / Jan Rhensius." Konstanz : Bibliothek der Universität Konstanz, 2011. http://d-nb.info/1017360499/34.
Full textFrougier, Julien. "Toward Spin-LED and Spin-VECSEL operations at magnetic remanence." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112175/document.
Full textThis Ph.D Thesis proposes to explore a new paradigm of spin-information propagation over very long distances after encoding on coherent light polarization. The main objective of this manuscript is to provide a detailed study of spin-injection into III-V semiconductor based opto-electronic devices with vertical geometries. To achieve this goal, we focus on the study of optical and electrical spin-injection in III-V semiconductor based Light Emitting Diodes (LEDs) and Vertical External Cavity Surface Emitting Lasers (VECSELs). Our investigations and results are presented on three axes.The first part regroups a state-of-the-art of spin-injection into semiconductors optoelectronic devices and focuses on the physical phenomena engaged in the conversion of a spin accumulation into light polarization information. A discussion on spin-injection and spin-transport into III-V semiconductor structures is followed by a more device-oriented review on spin-injection in LEDs and VCSELs.The second axis is articulated around our experimental work on the development and the optimization on III-V semiconductors LEDs of an ultra-thin MgO/CoFeB/Ta spin-injector with perpendicular magnetization at magnetic remanence. We focus on the MgO tunnel barrier optimization for maximizing the spin-injection efficiency and further detailed the development and the characterization of the spin-injector with perpendicular magnetization at remanence.Finally, the third part contains the main work of this Ph.D thesis. It is fully dedicated to our experimental research on spin-injection in Vertical External Cavity Surface Emitting Laser structures. A vectorial model allowing the theoretical understanding of polarization selection in spin-injected VECSELs is first introduced. Next, we report the birefringence measurement of a VECSEL designed for optical pumping using an original frequency detuning measurement between the two orthogonal TE- and TM-modes. Afterward, our observations and results on optical spin-injection in VECSELs are displayed, analyzed and commented. The study is farther extended to the measurement of the system's characteristic lifetimes using Time Resolved Photo-Luminescence in order to evaluate the spin-information conversion efficiency. Finally the preliminary results on electrical spin-injection experiment are presented
Skinner, Timothy. "Electrical control of spin dynamics in spin-orbit coupled ferromagnets." Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/247392.
Full textHamley, Christopher David. "Spin-nematic squeezing in a spin-1 Bose-Einstein condensate." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/47523.
Full textWulfhorst, Jeannette [Verfasser]. "Nonlocal spin currents in mesoscopic metallic spin valves / Jeannette Wulfhorst." München : Verlag Dr. Hut, 2012. http://d-nb.info/1028783183/34.
Full textCunningham, Elizabeth Sarah. "The effect of spin-spin interactions on nucleon-nucleus scattering." Thesis, University of Surrey, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527010.
Full textOzerov, Mykhaylo. "High-field electron spin resonance in low-dimensional spin systems." Doctoral thesis, Helmholtz-Zentrum Dresden-Rossendorf, 2010. https://tud.qucosa.de/id/qucosa%3A25598.
Full textHuang, Meng-Zi. "Spin squeezing and spin dynamics in a trapped-atom clock." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS134.
Full textAtomic sensors are among the best devices for precision measurements of time, electric and magnetic fields, and inertial forces. However, all atomic sensors that utilise uncorrelated particles are ultimately limited by quantum projection noise, as is already the case for state-of-the-art atomic clocks. This so-called standard quantum limit (SQL) can be overcome by employing entanglement, a prime example being the spin-squeezed states. Spin squeezing can be produced in a quantum non-demolition (QND) measurement of the collective spin, particularly with cavity quantum electrodynamical (cQED) interactions. In this thesis, I present the second-generation trapped-atom clock on a chip (TACC) experiment, where we combine a metrology-grade compact clock with a miniature cQED platform to test quantum metrology protocols at a metrologically-relevant precision level. In a standard Ramsey spectroscopy, the stability of the apparatus is confirmed by a fractional frequency Allan deviation of 6E-13 at 1 s. We demonstrate spin squeezing by QND measurement, reaching 8(1) dB for 1.7E4 atoms, currently limited by decoherence due to technical noise. Cold collisions between atoms play an important role at this level of precision, leading to rich spin dynamics. Here we find that the interplay between cavity measurements and collisional spin dynamics manifests itself in a quantum amplification effect of the cavity measurement. A simple model is proposed, and is confirmed by initial measurements. New experiments in this direction may shed light on the surprising many-body physics in this sytem of interacting cold atoms
Денисов, Станіслав Іванович, Станислав Иванович Денисов, Stanislav Ivanovych Denysov, and V. V. Shchotkin. "Influence of Spin-polarized Current on Spin Waves in Ferromagnets." Thesis, Sumy State University, 2018. http://essuir.sumdu.edu.ua/handle/123456789/67944.
Full textShaikh, Yasin Shadi. "Electron spin resonance in low-dimensional spin chains and metals." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-38273.
Full textLiu, Yi. "Dynamics, Synchronization and Spin Squeezing in a Two-Spin Model." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112216.
Full textThis thesis focuses on the dynamics of a cold atomic system which consists of two internalstates of atoms trapped in a magnetic trapping potential. The motivation of this thesis is aseries of experiments on such system carried out in 2010, where a surprising longcoherence time between the two internal states were observed. This phenomenon wasexplained by the kinetic theory which has used a mean-field approach. In this thesis, wetry to use a different approach and study the effects of quantum correlations in thedynamics of the system. In addition to that, we are also interested in the phenomenon ofspin squeezing which is the redistribution of quantum fluctuations in the spin system. Inorder to study the effects of the quantum correlations, we propose a simplified which splitsthe cold atoms into two groups based on their orbital movement energies in the trappingpotential and treat each group as a macro-spin. The main ingredients in this model are theinhomogeneity of the external field which dephases the two macro-spins and theexchange interaction between the two macro-spins, which mimics the identical spinrotation effect (ISRE), with the initial condition that the two spins lie parallel in thetransverse plane of the external field. Then we study the classical dynamics of the systemwhere the dynamics do not depend on the size of the spins and a synchronizationtransition is found when the exchange interaction is larger than the threshold, the half ofthe inhomogeneity of the external field. A phase space analysis reveals that thissynchronization transition is related to a bifurcation transition and the initial condition. Thenthe quantum dynamics is studied where the spin size plays an important role in thedynamics. There is no synchronization transition in the quantum systems and very richdynamical behavior is found. In the quantum dynamics, many characteristic time scalesemerge as the size of spin is increased, which are of quantum origin. These time scales isdependent of the spin size and all become infinite when the size of spin is infinite. In theway, the classical limit is recovered. Based on the strength of the exchange interaction,two effective models are proposed to calculate the smallest quantum characteristic timescales, which give very good agreement with the numerical results. Spin squeezing is alsostudied with these effective models
Bailleul, Matthieu. "Propagation et confinement d'ondes de spin dans les microstructures magnétiques." Phd thesis, Ecole Polytechnique X, 2002. http://tel.archives-ouvertes.fr/tel-00001976.
Full texthaute fréquence (GHz). Dans ce but, un spectromètre hyperfréquence à antennes micrométriques a été mis au point. Cet
instrument a été utilisé pour explorer deux problématiques différentes. Pour un film continu, d'abord, nous avons réalisé des
expériences d'émission-réception d'ondes de spin. Ces résultats nous ont permis de caractériser les processus de
transduction et de relaxation d'ondes magnétostatiques progressives. Nous avons également étudié des rubans de largeur
micrométrique, pour lesquels l'équilibre lui-même est inhomogène. Nous avons interprété leur réponse hyperfréquence en
termes de transitions de phase micromagnétiques et en termes de confinement d'ondes de spin.
Rennie, Adam Charles. "Noncommutative spin geometry." Title page, contents and introduction only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phr4163.pdf.
Full textMantke, Wolfgang. "Spin and gravity." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/27605.
Full textHijano, Cubelos Eliot. "Higher spin gravity." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110694.
Full textCette thèse s'intéresse aux théories gravitationnelles couplées à des spins entiers avec une constante cosmologiquenégative, dont l'origine provient de l'étude du groupe de jauge sl_N. La gravitation dans l'espace tridimensionnel anti de Sitter est d'abord décrite de manière semi-classique et la dualité avec la théorie conforme de champs en deux dimensions est ensuite présentée. L'exposition des solutions de la théorie N=3 permet la caractérisation des trous noirs par les propriétés des holonomies autour de boucles non-contractiles. L'invariance de jauge rapproche alors ces solutions aux trous noirs BTZ avec une charge d'un champ Chern-Simons. Néanmoins, la géometrie de l'espace-temps dépend du plongement des symétries gravitationnelles SL(2,R) dans le groupe de jauge SL(N,R). Le spectre des solutions est calculé pour tous ces plongements, et la condition de positivité exclut alors tous les cas sauf le plongement principal.
Lewis, C. "Spin(7) instantons." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301867.
Full text