Bibliographies thématiques / Ferromagnetic Quantum Dots

Littérature scientifique sur le sujet « Ferromagnetic Quantum Dots »

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Publié le 7 septembre 2023

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Articles de revues sur le sujet "Ferromagnetic Quantum Dots"

GAO, PAN, SUHANG LIU, LIN TIAN et TIANXING MA. « QUANTUM MONTE CARLO STUDY OF MAGNETIC CORRELATION IN GRAPHENE NANORIBBONS AND QUANTUM DOTS ». Modern Physics Letters B 27, n^o 21 (11 août 2013) : 1330016. http://dx.doi.org/10.1142/s0217984913300160.

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To realize the application of spintronics, possible magnetism in graphene-based material is an important issue to be addressed. At the tight banding level of armchair graphene nanoribbons, there are two flat bands in the band structure, two Van Hove singularities in the density of states, and the introducing of the next-nearest-neighbor hopping term cause high asymmetry in them, which plays a key role in the behavior of magnetic correlation. We further our studies within determinant quantum Monte Carlo simulation to treat the electron–electron interaction. It is found that the armchair graphene nanoribbons show carrier mediated magnetic correlation. In the armchair graphene nanoribbons, the antiferromagnetic correlation dominates around half filling, while the ferromagnetic correlation dominates as electron filling is lower than 0.8. Moreover, the ferromagnetic correlation is strengthened markedly as the next-nearest-neighbor hopping energy increases. The resultant manipulation of ferromagnetism in graphene-based material may facilitate the development of spintronics.

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Omariy, Aiman Al, et Reim Almotiriz y. « QUANTUM DOTS IN FERROMAGNETIC HEISENBERG MODEL ». EPH - International Journal of Applied Science 2, n^o 4 (27 décembre 2016) : 1–5. http://dx.doi.org/10.53555/eijas.v2i4.24.

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Quantum Dots (QDs) are semiconductor-nanostructure materials which are also called arti cial atoms. QDs are classi ed as ferromagnetic material. Theoretically, Heisenberg model is regarded as a good model in describing these QDs. We applied Spin Wave Theory (SWT) on the above mentioned model to explore the physical properties of these materials, such as ground state energy, excitation energy and magnetization. We found that the ground state energy "g increased with the applied external magnetic eld B as B0:3. A phase transition was also observed around B~1T, which indicate a transition from singlet to a triplet state. Staggered magnetization reaches saturation around this point of transition.

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Ma, Xi Ying. « Fabrication of Ferromagnetic Ge Quantum Dots Material ». Advanced Materials Research 531 (juin 2012) : 71–74. http://dx.doi.org/10.4028/www.scientific.net/amr.531.71.

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GeMn magnetic quantum dots (QDs) material were grown with a GeH4/Ar mixed gas under a constant flowing at 400°C by means of plasma enhanced chemical vapor deposition (PECVD) process, then doped with Mn doped using magnetic sputtering technique and annealed at 600 C. The QDs with a Ge0.88Mn0.12 structure derived from the energy spectrum show a wide opening hysteresis loops with a large remnant magnetizations Mr are 0.1410-4 and 0.2510-4 emu/g for the as grown and the annealed samples. Moreover, the magnetic QDs show high quality voltage-current (I-V) and voltage-capacitance (C-V) properties. The magnetic GeMn QDs can be used to fabrication electromagnetic devices.

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Xiu, Faxian. « Magnetic Mn-Doped Ge Nanostructures ». ISRN Condensed Matter Physics 2012 (7 mai 2012) : 1–25. http://dx.doi.org/10.5402/2012/198590.

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With the seemly limit of scaling on CMOS microelectronics fast approaching, spintronics has received enormous attention as it promises next-generation nanometric magnetoelectronic devices; particularly, the electric field control of ferromagnetic transition in dilute magnetic semiconductor (DMS) systems offers the magnetoelectronic devices a potential for low power consumption and low variability. Special attention has been given to technologically important group IV semiconductor based DMSs, with a prominent position for Mn doped Ge. In this paper, we will first review the current theoretical understanding on the ferromagnetism in MnxGe1−x DMS, pointing out the possible physics models underlying the complicated ferromagnetic behavior of MnxGe1−x. Then we carry out detailed analysis of MnxGe1−x thin films and nanostructures grown by molecular beam epitaxy. We show that with zero and one dimension quantum structures, superior magnetic properties of MnxGe1−x compared with bulk films can be obtained. More importantly, with MnxGe1−x nanostructures, such as quantum dots, we demonstrate a field controlled ferromagnetism up to 100 K. Finally we provide a prospective of the future development of ferromagnetic field effect transistors and magnetic tunneling junctions/memories using dilute and metallic MnxGe1−x dots, respectively. We also point out the bottleneck problems in these fields and rendering possible solutions to realize practical spintronic devices.

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MA, QIONG, TAO TU, LI WANG, HAI-OU LI, ZHI-RONG LIN, MING XIAO et GUO-PING GUO. « SUBSTRATE MODULATED GRAPHENE QUANTUM DOTS ». Modern Physics Letters B 26, n^o 25 (7 septembre 2012) : 1250162. http://dx.doi.org/10.1142/s021798491250162x.

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We propose a method to use gapped graphene as barriers to confine electrons in gapless graphene and form a good quantum dot, which can be realized on an oxygen-terminated SiO 2 substrate partly hydrogen-passivated. In particular, we use deposited ferromagnetic insulators as contacts which give rise to spin-dependent energy spectrum and transport properties. Furthermore, we upgrade this method to form two-dimensional quantum dot arrays, whose coupling strength between neighboring dots can be uniquely anisotropic. Compared to complexity of other approaches to form quantum dot in graphene, the setup suggested here is a promising candidate for practical applications.

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Xiu, Faxian, Igor V. Ovchinnikov, Pramey Upadhyaya, Kin Wong, Xufeng Kou, Yi Zhou et Kang L. Wang. « Voltage-controlled ferromagnetic order in MnGe quantum dots ». Nanotechnology 21, n^o 37 (20 août 2010) : 375606. http://dx.doi.org/10.1088/0957-4484/21/37/375606.

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Ramlan, Dinna G., Steven J. May, Jian-Guo Zheng, Jonathan E. Allen, Bruce W. Wessels et Lincoln J. Lauhon. « Ferromagnetic Self-Assembled Quantum Dots on Semiconductor Nanowires ». Nano Letters 6, n^o 1 (janvier 2006) : 50–54. http://dx.doi.org/10.1021/nl0519276.

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Yang, J. Y., K. S. Yoon, Y. H. Do, C. O. Kim, J. P. Hong, Y. H. Rho et H. J. Kim. « Ferromagnetic quantum dots formed by external laser irradiation ». Journal of Applied Physics 93, n^o 10 (15 mai 2003) : 8766–68. http://dx.doi.org/10.1063/1.1558600.

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Yan, Wensheng, Qinghua Liu, Chao Wang, Xiaoyu Yang, Tao Yao, Jingfu He, Zhihu Sun et al. « Realizing Ferromagnetic Coupling in Diluted Magnetic Semiconductor Quantum Dots ». Journal of the American Chemical Society 136, n^o 3 (10 janvier 2014) : 1150–55. http://dx.doi.org/10.1021/ja411900w.

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Martinek, J., Y. Utsumi, H. Imamura, J. Barnaś, S. Maekawa et G. Schön. « Kondo effect in quantum dots coupled to ferromagnetic electrodes ». Physica E : Low-dimensional Systems and Nanostructures 18, n^o 1-3 (mai 2003) : 75–76. http://dx.doi.org/10.1016/s1386-9477(02)00980-3.

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Thèses sur le sujet "Ferromagnetic Quantum Dots"

So, Tak Ki. « MBE-grown Fe ferromagnetic quantum dots / ». View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202003%20SO.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.
Includes bibliographical references (leaves 61-62). Also available in electronic version. Access restricted to campus users.

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Kolb, Paul Walter. « Cryogenic near-field scanning optical microscopy : quantum dots, charge-ordered domains, and ferromagnetic nucleation / ». College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1497.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2004.
Thesis 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.

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Lok, Shu Kin. « MBE grown Fe-based nanostructures / ». View abstract or full-text, 2010. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202010%20LOK.

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Cubaynes, Tino. « Shaping the spectrum of carbon nanotube quantum dots with superconductivity and ferromagnetism for mesoscopic quantum electrodynamics ». Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS195/document.

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Dans cette thèse, nous étudions des circuits de boîtes quantiques à base de nanotubes de carbone intégrés dans une cavité micro-onde. Cette architecture générale permet de sonder le circuit en utilisant simultanément des mesures de transport et des techniques propre au domaine de l’Electrodynamique quantique sur circuit. Les deux expériences réalisées durant cette thèse exploitent la capacité des métaux de contact à induire des corrélations de spins dans les boites quantiques. La première expérience est l’étude d’une lame s´séparatrice à paires de Cooper, initialement imaginée comme une source d’électrons intriqués. Le couplage du circuit aux photons dans la cavité permet de sonder la dynamique interne du circuit, et a permis d’observer des transitions de charge habillées par le processus de séparation des paires de Cooper. Le couplage fort entre une transition de charge dans un circuit de boîtes quantiques et des photons en cavité, a été observée pour la première fois dans ce circuit. Une nouvelle technique de fabrication a aussi été développé pour intégrer un nanotube de carbone cristallin au sein du circuit de boîtes quantiques. La pureté et l’accordabilité de cette nouvelle génération de circuit a rendu possible la seconde expérience. Cette dernière utilise deux vannes de spins non colinéaire aﬁn de produire une interface cohérente entre le spin d’un électron dans une double boite quantique, et un photon dans une cavité. Des transitions de spins très cohérentes ont été observée, et nous donnons un modèle sur l’origine de la décohérence du spin comprenant le bruit en charge et les ﬂuctuations des spins nucléaires
In this thesis, we study carbon nanotubes based quantum dot circuits embedded in a microwave cavity. This general architecture allows one to simultaneously probe the circuit via quantum transport measurements and using circuit quantum electrodynamics techniques. The two experiments realized in this thesis use metallic contacts of the circuit as a resource to engineer a spin sensitive spectrum in the quantum dots. The ﬁrst one is a Cooper pair splitter which was originally proposed as a source of non local entangled electrons. By using cavity photons as a probe of the circuit internal dynamics, we observed a charge transition dressed by coherent Cooper pair splitting. Strong charge-photon coupling in a quantum dot circuit was demonstrated for the ﬁrst time in such a circuit. A new fabrication technique has also been developed to integrate pristine carbon nanotubes inside quantum dot circuits. The purity and tunability of this new generation of devices has made possible the realization of the second experiment. In the latter, we uses two non-collinear spin-valves to create a coherent interface between an electronic spin in a double quantum dot and a photon in a cavity. Highly coherent spin transitions have been observed. We provide a model for the decoherence based on charge noise and nuclear spin ﬂuctuations

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Siqueira, Ezequiel Costa. « Transporte por reflexão de Andreev em pontos quânticos duplos acoplados a eletrodos supercondutores e ferromagnéticos ». [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277834.

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Orientador: Guillermo Gerardo Cabrera Oyarzun
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-09-24T19:09:49Z (GMT). No. of bitstreams: 1 Siqueira_EzequielCosta_D.pdf: 16155551 bytes, checksum: 43337169b3f9ac0ffbe444e3859ff790 (MD5) Previous issue date: 2010
Resumo: Neste trabalho é estudado o transporte quântico em nanoestruturas híbridas compostas por pontos quânticos (PQ) duplos acoplados a eletrodos supercondutores (S) e ferromagnéticos (F). A primeira nanoestrutura, denotada por F - PQa - PQb - S consiste em dois PQs em série acoplados a um eletrodo ferromagnético e outro supercondutor. O segundo sistema, denotado por (F1, F2) - PQa - PQb - S consiste em dois PQs em série acoplados a dois eletrodos ferromagnéticos e um supercondutor. Através do método de funções de Green de não equilíbrio foram obtidas expressões para a corrente elétrica, condutância diferencial, densidade local de estados (LDOS) e a transmitância para energias inferiores ao gap supercondutor. Neste regime, o mecanismo de transmissão de carga é a reflexão de Andreev, a qual permite controlar a corrente através da polarização do ferromagneto. A presença de interações nos PQs é considerada usando um tratamento de campo médio. Para o sistema F - PQa - PQb - S, as interações tendem a localizar os elétrons nos PQs levando a um padrão assimétrico da LDOS reduzindo a transmissão através da nanoestrutura. Em particular, a interação intra PQ levanta a degenerescência de spin reduzindo o valor máximo da corrente devido ao desequilíbrio nas populações de spin up e spin down. Regiões de condutância diferencial negativa (CDN) aparecem em determinados valores do potencial aplicado, como resultado da competição entre o espalhamento Andreev e as correlações eletrônicas. Aplicando-se um potencial de gate nos pontos quânticos é possível sintonizar o efeito mudando a região onde este fenômeno ocorre. Para o sistema (F1, F2) - PQa - PQb - S observou-se que o sinal da magnetoresistência pode mudar de positivo para negativo mudando-se o sinal do potencial aplicado. Além disso é possível controlar a corrente no primeiro eletrodo mudando-se o valor do potencial no segundo ferromagneto. Este tipo de controle pode ser interessante do ponto de vista de aplicações desde que é um comportamento similar a um transistor. Na presença de interações nos PQs, observou-se novamente regiões de CDN para determinados valores do potencial aplicado mesmo para quando os ferromagnetos estão completamente polarizados. Desta forma, a interação entre supercondutividade e correlações eletrônicas permitiu observar fenômenos originais mostrando que este sistemas podem ser utilizados em aplicações tecnológicas futuras
Abstract: In this work we studied the quantum transport in two hybrid nanostructures composed of double quantum dots (DQD)s coupled to superconductor (S) and ferromagnetic (F) leads. The first nanostructure, denoted by F - QDa - QDb - S, is composed of a ferromagnet, two quantum dots, and a superconductor connected in series. In the second nanostructure, denoted by ( F1, F2) - QDa - Q Db - S, a second ferromagnetic lead is added and coupled to the first QD. By using the non-equilibrium Green's function approach, we have calculated the electric current, the differential conductance and the transmittance for energies within the superconductor gap. In this regime, the mechanism of charge transmission is the Andreev re°ection, which allows for a control of the current through the ferromagnet polarization. We have also included interdot and intradot interactions, and have analyzed their influence through a mean field approximation. For the F - QDa - QDb - S system the presence of interactions tend to localize the electrons at the double-dot system, leading to an asymmetric pattern for the density of states at the dots, and thus reducing the transmission probability through the device. In particular, for non-zero polarization, the intradot interaction splits the spin degeneracy, reducing the maximum value of the current due to different spin-up and spin-down densities of states. Negative differential conductance (NDC) appears for some regions of the voltage bias, as a result of the interplay of the Andreev scattering with electronic correlations. By applying a gate voltage at the dots, one can tune the effect, changing the voltage region where this novel phenomenon appears. In the (F1, F2) - QDa - QDb - S, we have found that the signal of the magnetoresistance can be changed through the external potential applied in the ferromagnets. In addition, it is possible to control the current of the first ferromagnet (F1) through the potential applied in the second one (F2). This transistor-like behavior can be useful in technological applications. In the presence of interaction at the dots it was observed the NDC effect even when the electrodes were fully polarized. The results presented in this thesis show that the interplay between the superconductor correlation and electronic interactions can give rise to original effects which can be used in future technological applications
Doutorado
Física da Matéria Condensada
Doutor em Ciências

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Ou, Yi-Ching, et 歐逸青. « Probing physical properties in nanostructures : I. Collective transport in self-assembled PbSe quantum dot arrays II. Ferromagnetism in Zn1-xCoxO nanowires ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/91556339764734268555.

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博士
國立交通大學
物理研究所
99
In the thesis we study three physical phenomena in nanostructures: self-assembly of PbSe quantum dot array, collective transport in PbSe quantum dot arrays, and ferromagnetism in Zn1-xCoxO nanowires. Semiconductor quantum dots with diameters of several to tens of nanometers have been largely synthesized through colloidal techniques for nanoscience exploration of quantum confinement, Coulomb staircase, and artificial-atom states in individual quantum dots and self-assembling growth behavior. To learn about the underlying physics of self-assembly, growth mechanisms, and coupling-induced collective properties, here we report a facile way of preparing nanocrystal-assembled 2D islands by drop-casting nanocrystal suspension on a hot substrate. Growth mechanisms such as scaling function, spinodal decomposition phase separation, and diffusion-limited aggregation are investigated based on the observation of quasi-monolayer coverage. After a curve fitting to several theoretical growth models, the pair bond (interaction) energy, critical nucleus size, and the phase of growth patterns were determined. Moreover, by heating the substrate and controlling the concentration of nanocrystal suspension, the spinodal decomposition and diffusion-limited aggregation can be tuned to modulate growth patterns of 2D nanocrystal islands. The interplay of these two mechanisms results in a variation of wavelength in spinodal growth patterns and of fractal pattern dimensions. By using this experimental approach, various sizes and shapes of nanocrystal-assembled 2D islands can be deposited on a flat surface of either graphite or gold. Although charge transport of three-dimensional quantum dot arrays has been attempted for study on the micron scale, the electrical properties of a nanoscale array, self-assembled from a single quantum dot through a bottom-up procedure, have not been explored yet. Inter-dot Coulomb interactions and collective Coulomb blockade were theoretically argued to be a newly important topic, and experimentally identified in semiconductor quantum dots. To study the interdot coupling, we control growth parameters to self-assemble different sizes of PbSe quantumdot arrays on flat gold surface for scanning tunneling spectroscopy measurements at both room and liquid-nitrogen temperatures. The current-voltage curves of the arrays are analyzed using a double-barrier tunnel junction model to acquire the shunt capacitance between the array and the gold substrate. The increment of this capacitance is small as the particle number increases extremely from 1 to 80. Thus the array cannot be taken as a simple semiconductor island. The tip-to-array, array-to-substrate, and interdot capacitances are evaluated and the tunneling spectra of quantum-dot arrays are analyzed by the theory of collective Coulomb blockade. The current–voltage of PbSe quantum-dot arrays conforms properly to a scaling power law function. The dependence of tunneling spectra on the sizes (numbers of quantum dots) of arrays is reported and the capacitive coupling between quantum dots in the arrays is explored. In the topic of ferromagnetism in Zn1-xCoxO nanowires, diameter controllable ZnO nanowires have been fabricated by thermal evaporation (vapor transport) with various sizes of gold nanoparticles as catalysts. Diluted magnetic semiconductor (DMS) Zn1-xCoxO nanowires were then made by high energy Co ion implantation. The morphology and crystal structure of the nanowires were inspected by use of scanning and transmission electron microscopes. Magnetic properties of the Zn1-xCoxO nanowires were measured by employing a SQUID magnetometer. The as-implanted Zn1-xCoxO nanowires displayed weak ferromagnetism and size dependent behavior has been observed in the magnetic field and temperature dependences of magnetization. The shrinkage of the nanowire diameter reduced the spontaneous magnetization as well as the hysteresis loops. After high-vacuum annealing, Zn1-xCoxO nanowires exhibited strong ferromagnetic ordering at room temperature. Electron microscopy analysis was used to ensure the absence of Co nanocrystals in the annealed nanowires. The effect of annealing on the creation of a strong ferromagnetic state is much more pronounced in thinner nanowires. From field cooled and zero-field cooled magnetization and coercivity measurements between 2 and 300 K, superparamagnetic features were observed in the Zn1-xCoxO nanowires. We argue that the generation of point defects by vacuum annealing is the origin for the enhanced ferromagnetism in the Zn1-xCoxO nanowires. We employed magnetic force microscopy to verify the ferromagnetism in individual Zn1-xCoxO nanowires. Two kinds of domain structure, transverse and longitudinal, were observed in ferromagnetic nanowires and the magnetic dipole moment of individual nanowires was estimated by fitting to a two magnetic point dipole moment model.

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Chapitres de livres sur le sujet "Ferromagnetic Quantum Dots"

König, Jürgen, Matthias Braun et Jan Martinek. « Manipulating Single Spins in Quantum Dots Coupled to Ferromagnetic Leads ». Dans CFN Lectures on Functional Nanostructures - Volume 2, 103–24. Berlin, Heidelberg : Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-14376-2_6.

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König, Jürgen, Jan Martinek, Józef Barnaś et Gerd Schön. « Quantum Dots Attached to Ferromagnetic Leads : Exchange Field, Spin Precession, and Kondo Effect ». Dans CFN Lectures on Functional Nanostructures Vol. 1, 145–64. Berlin, Heidelberg : Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-31533-9_7.

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Sutton, Adrian P. « Small is different ». Dans Concepts of Materials Science, 81–93. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780192846839.003.0007.

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As the size of a material decreases to the nanoscale its properties become size-dependent. This is the world of nanoscience and nanotechnology. At the nanoscale the crystal structure may change and thermodynamic quantities such as the melting point also change. Changes in the catalytic activity and colour of nanoparticles suspended in a liquid indicate changes to the electronic structure. Quantum dots have discrete energy levels that can be modelled with the particle-in-a-box model. Excitons may be created in them using optical illumination, and their decay leads to fluorescence with distinct colours. The classical and quantum origins of magnetism are discussed. The origin of magnetoresistance in a ferromagnet is described and related to the exclusion principle. The origin of the giant magnetoresistance effect and its exploitation in nanotechnology is outlined.

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Zinn-Justin, Jean. « Lattice gauge theories : Introduction ». Dans Quantum Field Theory and Critical Phenomena, 607–22. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834625.003.0025.

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Lattice gauge theories are based on the notion of parallel transport. They can be considered as non-perturbative regularizations of the continuum gauge theories in the sense of a low-temperature expansion. The chapter is mainly devoted on a study of matterless lattice gauge theories from the point of view of phase transitions. This means many properties of a realistic theory like quantum chromodynamics (QC) cannot be investigated, but the important question of confinement can still be studied: does the theory generate a force between charged particles increasing at large distances, so that heavy quarks in the fundamental representation cannot be separated? More generally, can one find charged asymptotic states like massless vector particles in the theory? Lattice gauge theories have properties quite different from the ferromagnetic systems. In particular the absence of a local order parameter requires a study of the behaviour of a non-local quantity, a functional of loops generally called Wilson's loop, to distinguish between the confined and deconfined phases, characterized by an area or perimeter law, respectively.

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Actes de conférences sur le sujet "Ferromagnetic Quantum Dots"

STOPA, M. « FERROMAGNETIC AND ANTI-FERROMAGNETIC RECONSTRUCTION IN SEMICONDUCTOR QUANTUM DOTS ». Dans Proceedings of the 7th International Symposium. WORLD SCIENTIFIC, 2002. http://dx.doi.org/10.1142/9789812776716_0038.

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MATSUBAYASHI, D., et M. ETO. « KONDO EFFECT IN QUANTUM DOTS COUPLED WITH NONCOLLINEAR FERROMAGNETIC LEADS ». Dans Proceedings of the International Symposium. WORLD SCIENTIFIC, 2008. http://dx.doi.org/10.1142/9789812814623_0036.

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Ferri, Fabio A., Vasyl P. Kunets, Gregory J. Salamo et Euclydes Marega Jr. « Ordering ferromagnetic In[sub 1−x]Mn[sub x]As quantum dots ». Dans THE PHYSICS OF SEMICONDUCTORS : Proceedings of the 31st International Conference on the Physics of Semiconductors (ICPS) 2012. AIP, 2013. http://dx.doi.org/10.1063/1.4848433.

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Liu, Haoliang, B. X. Du, Meng Xiao et Ke Chen. « Ferromagnetic Quantum Dots Improving Dielectric Properties of Polypropylene Film in Magnetic Field ». Dans 2022 IEEE International Conference on High Voltage Engineering and Applications (ICHVE). IEEE, 2022. http://dx.doi.org/10.1109/ichve53725.2022.9961607.

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Matsubayashi, Daisuke, et Mikio Eto. « Kondo effect in quantum dots coupled to ferromagnetic leads : effect of noncollinear magnetization ». Dans PHYSICS OF SEMICONDUCTORS : 28th International Conference on the Physics of Semiconductors - ICPS 2006. AIP, 2007. http://dx.doi.org/10.1063/1.2730135.

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Chirla, Razvan, Ireneusz Weymann, Piotr Trocha et Cătălin Paşcu Moca. « The SU(4) Kondo effect in double quantum dots coupled to ferromagnetic leads : A scaling analysis ». Dans TIM 18 PHYSICS CONFERENCE. Author(s), 2019. http://dx.doi.org/10.1063/1.5090063.

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Bersano, Fabio, Michele Aldeghi, Eloi Collette, Michele Ghini, Franco De Palma, Fabian Oppliger, Pasquale Scarlino et al. « Quantum Dots Array on Ultra-Thin SOI Nanowires with Ferromagnetic Cobalt Barrier Gates for Enhanced Spin Qubit Control ». Dans 2023 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits). IEEE, 2023. http://dx.doi.org/10.23919/vlsitechnologyandcir57934.2023.10185278.

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Hee Chang Jeon, Youn Seek Jeong, Kwang Jae Chung, Kwang Jo Chung, Tae Won Kang, Tae Whan Kim, Wanho Jhe et Se Ahn Song. « (In/sub 1-x/Mn/sub x/)As diluted diluted magnetic semiconductor quantum dots with above room ferromagnetic transition temperature ». Dans Proceedings of MBE-XII. IEEE, 2002. http://dx.doi.org/10.1109/mbe.2002.1037737.

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Kumar, D., J. Sankar, J. Narayan et A. Kvit. « Tunable Magnetic and Mechanical Properties in Metal Ceramic Composite Thin Films ». Dans ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/md-24805.

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Abstract Presently a wide spread of research activities is pursued in the area of theoretical, computational and experimental aspects of vibration studies in laminated composite structures with embedded or surface bonded smart layers in order to improve the performance of components in aerospace, mechanical, robotics, and electronic equipments. The key to the successful fabrication of these components with improved properties is the development of smart materials by materials engineering and understanding the fundamentals of materials science. It is in this context that we have developed a novel smart thin film processing method based upon pulsed laser deposition to process nanocrystalline materials with accurate size and interface control with improved mechanical and magnetic properties. Using this method, single domain nanocrystalline Fe and Ni particles in 5–10 nm size range embedded in amorphous as well as crystalline alumina have been produced. By controlling the size distribution in confined layers, it was possible to tune the magnetic properties from superparamagnetic to ferromagnetic in a controlled way. Magnetization measurements of these thin film composites as function of field and temperature were carried out using a superconducting quantum interference device (SQUID) magnetometer. Magnetic hysteresis characteristics below the blocking temperature are consistent with single-domain behavior. Mechanical properties were measured using nano-indentation measurements. The hardness of the Fe and Ni-Al2O3 nanocomposites was found to vary strongly with the size do Fe and Ni nanodots in the alumina matrix. For example, the hardness of Fe-Al2O3 system increased from 15 GPa to 28 GPa when the size of Fe dots in alumina was increased from 5 nm to 9 nm. It is envisioned that this types of smart films can be used in magnetic recording, ferrofluid technology, magnetocaloric refrigeration, biomedicine, biotechnology, aerospace applications where hard and wear-resistant coatings are also very important for its survival.

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Machida, T., et K. Hamaya. « Spin Transport in a Single InAs Quantum Dot Attached to Ferromagnetic Electrodes (Invited) ». Dans 2008 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2008. http://dx.doi.org/10.7567/ssdm.2008.h-7-1.

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