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1
Sadeghzadeh, Kayvan. "Spin polarised Fermi gases." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610744.
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Allen, William D. "Aspects of spin polarised transport." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368082.
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Roskoss, Alexander. "Spin polarised metastable deexcitation spectroscopy." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434022.
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Blackwood, Elaine. "Spin polarised dynamics in quantum wells." Thesis, University of Southampton, 1993. https://eprints.soton.ac.uk/206553/.
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The ability to preferentially spin-polarise a photoexcited carrier population in a quantum well by optical pumping methods has enabled us to study the fine structure and some of the parameters governing the spin relaxation dynamics of excitons, heavy-holes and electrons in a number of type I GaAs/AlxGa1-xAs and type I InxGa1-xAs/GaAs single and multiple quantum wells. The electron, hole and excitonic effective Lande g-factors have been measured as a function of quantum well thickness in GaAs/Al0.36Ga0.64As and In0.11Ga0.89As/GaAs. For the GaAs/AlGaAs wells, we observed a change in sign of the exciton g-factor and using k.p perturbation theory to model the form of the electron g-factor, we obtained the hole g-factor as a function of well width. Both the electron and hole g-factors also exhibited a change in sign. In the case of the InGaAs/GaAs wells, the exciton g-factor was small and of positive magnitude for all the wells we studied. Describing the form of the electron g-factor by a strain modified k.p perturbation theory and using the measured exciton g-values, the hole g-factor was calculated to take small, but slightly more positive values than the exciton g-factor. The electron-hole exchange interactions have been measured in GaAs/Al0.36Ga0.64As and GaAs/A1As samples as a function of well width. In both cases the exchange splitting between the optically active and inactive levels was consistent with theory, falling rapidly with decreasing confinement towards the measured value for bulk GaAs. A finite exchange splitting of the optically active levels at zero field demonstrates the symmetry of the quantum well is less than Dja, possibly due to growth induced imperfections. We have measured the spin relaxation times of electrons, holes and excitons in GaAs/Al0.3Ga0.7As quantum wells. We observed a much shorter relaxation time for the excitons, lOOps, compared to the free electron and hole relaxation times which were both of the order of Ins. We have attributed the fast exciton spin relaxation to the strong exchange between the electron and hole forcing the more rapidly relaxing particle to govern the spin relaxation dynamics. Our results suggest that the hole is the more rapidly relaxing particle when confined in an exciton. We have attributed this rapid spin relaxation of the holes to the mixing of the light and heavy-hole bands for wavevectors away from k=0 in a quantum wells. We have also observed a strong temperature dependence of the hole relaxation time which is consistent with a wavevector dependence of the hole relaxation time. Finally we have direct measurements of the wavevector dependence of hole relaxation time and the reduction in this due to the mixing of the valence band states in a quantum well away from k=0.
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Nyman, Robert Andrew. "Spin dynamics of polarised fermi-liquid 3He." Thesis, University of Nottingham, 2003. http://eprints.nottingham.ac.uk/10042/.
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The spin-dynamics of Fermi-liquid helium-3 in pure form and in its mixtures with helium-4 are considered in this thesis. A linearised model of the spin dynamics is developed from Leggett's equation of motion, including spin-diffusion, the Leggett-Rice spin-rotation effect and cylindrical boundary conditions . The equations are solved using a matrix formalism, allowing simulation of FIDs, NMR spectra and spin-echoes. The boundary conditions are shown to cause deviations of spin-echo amplitude and phase from the predictions of Leggett and Rice, for realistic experiments. The model is extended to include the demagnetising field (dipolar field) due to the magnetisation of the sample itself. Simulations show that, when the demagnetising field is strong, spectral clustering is present and sharp peaks are observed in the NMR spectrum. Data from NMR experiments on 3He and 3He-4He mixtures in an 11.3T magnetic field, performed in Nottingham in 1999/2000, are analysed. The analysis of 6.2% 3He mixture is predominantly by least-squares fitting of the model (excluding demagnetising field) to spin-echo data, yielding the transverse spin-diffusion coefficient and spin-rotation parameter as functions of temperature down to 3.4mK. Parameters are seen to deviate from the 1/Ta^2 characteristic of Fermi-liquid transport parameters, with a 1/(T^2+Ta^2) form, indicative of spin-transport anisotropy. The anisotropy temperature scale Ta is found to be 6+-1 mK. Analysis of pure 3He experiments is by qualitative comparison of spectroscopic data with the model (including demagnetising field): many observed features are reproduced by the simulation.
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Matthews, M. T. "A study of nucleon spin structure through polarised muon polarised proton deep inelastic scattering." Thesis, University of Liverpool, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233868.
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Hope, S. "Spin polarised radiation studies of ultrathin magnetic films." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604219.
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Two distinct spin polarised radiation techniques have been employed to determine the magnetic properties of ultrathin magnetic films in-situ and ex-situ. The magneto-optical Kerr effect has been used to study the evolution of the magnetic properties during room temperature growth of Co/Cu(110) in -situ. The thickness dependence of the magnetic moment per atom in the Cu/Ni/Cu/Si(001) system has been investigated ex-situ using polarised neutron reflection. The Co/Cu(110) system is found to exhibit a 3D growth mode, becoming ferromagnetic at a critical thickness of dc=4.6±1.1. ML. Remarkably, the magnetic susceptibility χ follows a power law near dc with a critical exponent γ=2.39±0.08, which is in excellent agreement with the theoretical value of γ=2.43 for a 2D percolation phase transition. STM measurements on the same crystal indicate that the percolation phase transition is related to the coalescence of Co island clusters across the entire sample area. For a given Co thickness in the range 5ML
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Wightman, David Richard. "NMR properties of spin-polarised '3He-'4He solutions." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293656.
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Hampson, T. M. M. "Transport properties of dilute, spin-polarised fermi liquids." Thesis, University of Nottingham, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384305.
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Sinha, Priyasmita. "Highly spin-polarised chiral transition metal silicide epilayers." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/13071/.
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We have investigated the Co-doping dependence of the structural, transport, and magnetic properties of �-Fe1−xCoxSi epilayers grown by molecular beam epitaxy on silicon (111) substrates. Low energy electron diffraction, atomic force microscopy, X-ray diffraction, and high resolution transmission electron microscopy studies have confirmed the growth of phase pure, defect free �-Fe1−xCoxSi epitaxial films with a surface roughness of � 1 nm. These epilayers are strained due to lattice mismatch with the substrate,deforming the cubic B20 lattice so that it becomes rhombohedral. The temperature dependence of the resistivity changes as the Co concentration is increased, being semiconducting-like for low x and metallic for x less than 0.3. The films exhibit the positive linear magnetoresistance that is characteristic of �-Fe1−xCoxSi below their magnetic ordering temperatures (Tord), as well as the huge anomalous Hall effect of order several μcm. The ordering temperatures are higher than those observed in bulk, up to 77 K for x = 0.4. The saturation magnetic moment of the films varies as a function of Co doping, with a contribution of � 1 μB/ Co atom for x less than equal to 0.25. When taken in combination with the carrier density derived from the ordinary Hall effect, this signifies a highly spin-polarized electron gas in the low x, semiconducting regime. To understand the electronic structure and evolution of magnetism in B20 system we used soft X-ray absorption (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopy in total electron yield mode (TEY) to probe the L2,3 edges of Fe and Co in Fe1−xCoxSi thin films. Branching ratios (L3/(L2 + L3)) as a function of x, suggests that the number of holes associated with Co increases from x=0.1 to x=0.5 where as that associated with Fe changes little. Variation in the occupation states of Fe and Co atoms coupled with shift in L2,3 edges (� 500 meV ) and the evolution of the L3 edge line shape indicates a modified band structure. The dichroism on Fe L3 edge (TEY) varies from 0.6 × 10−3 for x=0.1 to 1.4 × 10−3 for x=0.5 and that of Co evolves from being negligible for x=0.1 to 1.7 × 10−3 for x=0.5. Whilst the magnetism in Fe1−xCoxSi system arises from the Co doping, these asymmetry spectra clearly show that the magnetic moment is delocalised on both Co and Fe sites.
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Bergmann, Kirsten von. "Iron nanostructures studied by spin-polarised scanning tunneling microscopy." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971962464.
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Jo, Moon-Ho. "Spin polarised tunnel junctions based on half-metallic manganites." Thesis, University of Cambridge, 2001. https://www.repository.cam.ac.uk/handle/1810/183622.
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Smith, Timothy John. "The application of spin polarised neutron scattering to superconductors." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/10465.
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The use of spin polarised neutron scattering as an experimental probe for magnetic phenomena within solid state physics has been demonstrated in two separate studies of superconductors. With the use of three-dimensional polarisation analysis, the magnetic response within a thermal energy window -30meV < Iiw < +30meV has been measured for both insulating and superconducting compositions of the high T c material YBa2Cu306+x. The observed magnetic scattering from the superconducting composition (x=0.9S, T c-90K) at T =300K shows conclusively that there is negligible magnetic scattering in the normal state below 30meV. What little scattering is observed corresponds to a paramagnetic cross-section of (0.048±0.008)barns or to -3.2% of the Cu atoms carrying a spin 1/2. Similar polarised neutron measurements performed on insulating YBa2Cu306.11, above and below TN, reveal a small but finite level of scattering corresponding to -18% of the Cu atoms carrying a spin 1/2 in the paramagnetic state. The observed increase in paramagnetic scattering above T N corresponds to just 20% of that expected due to the thermal disordering of the observed ordered magnetic moment at 300K. These measurements are consistent with a magnetic excitation spectrum driven by quantum rather than thermal fluctuations for which the notion of separate magnetic and charge degrees of freedom (and therefore also the concept of local moments) may not be valid. In addition, measurements conducted on single crystal YBa2Cu307 in its normal state revealed no indication of magnetic enhancement in the vicinity of the (It, It) point up to 30meV. This is in disagreement with theoretical predictions of an enhanced magnetic scattering in this region for spin fluctuation energies of order 10 to 20meV. The second study demonstrates the feasibility of spin polarised neutron scattering as a novel tool for the investigation of the flux line lattice in type 11 superconductors. Measurements conducted in the mixed state of niobium (T =4.SK, B=O.22T) constitute the first experimental observation of lattice distortions due to the presence of flux line vortices. The experimentally determined magnitude of the lattice distortion yields a value approximately three orders of magnitude greater than that expected due to the volume anomaly between the coexisting normal and superconducting regions. An alternative mechanism is suggested on the basis of electron redistribution between the normal and superconducting regions in which electrons are trapped by the flux lines. As a result of this process, a response in the form of a lattice distortion is induced in order to maintain charge neutrality.
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Schofield, Debra Mary. "Development of spin-polarised scanning tunnelling microscopy for the study of spin electronic materials." Thesis, University of York, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442379.
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Bebb, Andrew M. "Synchrotron radiation studies of spin-polarised electron momentum density distributions." Thesis, University of Warwick, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404845.
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Marshall, Ishbel. "Studies of novel organic and inorganic compounds using spin polarised muons." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437353.
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Schedin, Bernt Fredrik. "Angle-resolved spin-polarised inverse photoemission spectroscopy studies of Ni(110)." Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317198.
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Phillips, Lee Charles. "Spintronic devices with highly spin-polarised manganite electrodes and graphene channels." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610490.
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Pravica, Luka. "Polarised electron studies of spin-dependent interactions in zinc and krypton atoms." University of Western Australia. School of Physics, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0063.
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[Truncated abstract.] An apparatus has been built, tested and characterised with greatly increased precision and accuracy to enable spin-polarised electron impact explorations of angular momentum effects in atoms. A combination of experimental, computational and interpretative studies has revealed new phenomena. In zinc the polarisation of the radiated photons from excited and ionised-with-excited atoms was measured in terms of integrated Stokes parameters (P1, P2 and P3) and related to electron exchange and spin-orbit interaction using normalised state multipoles.
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Gehrmann, Thomas. "Proton structure from deep inelastic and diffractive scattering." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5224/.
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We investigate various aspects of the proton structure in this thesis. The first addresses the distribution of the proton spin among its constituents, quarks and gluons. We derive the framework of distribution functions for these constituents and study the properties of the polarized distributions which describe the spin structure of the proton. A determination of the polarized distributions on the basis of present experimental data is presented and options for future measurements are critically evaluated. A second aspect under consideration is the phenomenology of hard diffractive electron-proton scattering. We show how diffractive interaction and hard scattering can be disentangled and suggest experimental tests for this interpretation. Finally, we illustrate how the knowledge on the proton structure can be used for the computation of observables in proton-antiproton collisions, confirming or extending our knowledge of the physics of elementary particles.
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Kaiser, Ralf Bernd. "Measurement of the spin structure of the neutron using polarised deep inelastic scattering." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq24319.pdf.
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Allsworth, Max Daniel. "The effect of spin-polarised electrons on superconductivity in a ferromagnet superconductor bilayer." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273991.
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Kato, Takashi, Yasuhito Ishikawa, Hiroyoshi Itoh, and Jun-ichiro Inoue. "Intrinsic anisotropic magnetoresistance in spin-polarized two-dimensional electron gas with Rashba spin-orbit interaction." American Physical Society, 2008. http://hdl.handle.net/2237/11252.
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Martyniak-Stronczek, Aleksandra. "Using spin polarised positive muons for studying guest molecule partitioning in soft matter structures." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-29731.
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Linder, Jacob, Takehito Yokoyama, Yukio Tanaka, and Asle Sudbø. "Strongly spin-polarized current generated in a Zeeman-split unconventional superconductor." American Physical Society, 2008. http://hdl.handle.net/2237/11294.
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Evaldsson, Martin. "Spin splitting in open quantum dots and related systems." Licentiate thesis, Linköping : Linköpings universitet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4939.
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Nguyen, Ngoc-Minh. "Propagation de parois magnétiques dans des films et des pistes à anisotropie magnétique perpendiculaire." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112356.
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Cette thèse est consacrée à l’étude des mécanismes de propagation de parois magnétiques dans des films et des pistes magnétiques basés sur des matériaux à anisotropie magnétique perpendiculaire qui sont très prometteurs pour les mémoires magnétiques non volatiles d’ultra haute densité. Je me suis principalement intéressé à l’influence des défauts structuraux sur les mécanismes de dépiegeage de parois en utilisant la technique de microscopie Kerr ainsi que des mesures de transport. Trois résultats importants ont été mis en évidence : (1) Dans des vannes de spin de type CoNi/Cu/CoNi, il existe une forte influence du champ dipolaire généré par la couche dure qui peut influencer la nucléation parasite de paroi magnétique dans la couche libre et créer une propagation asymétrique sous l’effet d’un courant polarisé. J’ai aussi montré que dans des pistes sub-50nm, le renversement de l’aimantation s’effectue par des événements multiples de nucléation à cause de la présence de centres de piégeage fort qui bloquent la propagation ; (2) En visualisant la géométrie des domaines magnétiques et en étudiant les lois de reptation, j’ai montré la présence d’une faible densité de défauts structuraux et de faibles champs de propagation dans les multicouches texturés/amorphe de CoNi-CoFeB et cristallisés de Ta-CoFeB-MgO ; (3) J’ai finalement mis en évidence un effet du transfert de spin à de faibles densités de courant (≈5x1011 A/cm2) dans les pistes de CoNi-CoFeB. J’ai aussi montré une forte influence du champ d’Oesterd sur la propagation de parois liée à la présence de faibles champs de propagation. Finalement, dans le cas des pistes basées sur des films cristallisés de Ta-CoFeB-MgO, j’ai pu mesurer la vitesse sur 10 ordres de grandeur et montrer que les parois se propagent à des champs de propagation ultra faibles (0,1mT)This work is focused on the study of magnetic domain wall propagation mechanisms in the thin films and wires based on materials with perpendicular magnetic anisotropy which are promissing for the non-volatile magnetic memory of ultra high density. I’m interested in the influence of structural defects on the mechanisms of domain wall propagation by using the Kerr microscopy technique and the transport measurements. Three important results were obtained: (1) In the spin valve structure of CoNi/Cu/CoNi, a strong influence of the dipolar magnetic field induced by the hard layer can generate a parasitic nucleation in the soft layer and create an asymmetric domain wall propagation driven by a spin polarized current. I also demonstrated that in sub-50nm wires, the nature of magnetization reversal process is the multiple nucleation events because of strong pinning centers that hinder the domain wall motion; (2) By observing the magnetic domain geometry et studying the creep law, I have pointed out that in the CoNi-CoFeB multilayers and the crystallized Ta-CoFeB-MgO multilayers, the structural defect density is low and the propagation fields can be reduced; (3) I found a spin-transfer effect with low current density (≈5x1011 A/cm2) in CoNi-CoFeB wires. I also demonstrated that the Oersted field can strongly influence the domain wall motion, especially in the material with low propagation field. Finally, in the Ta-CoFeB-MgO wires, I could measure a wide range of domain wall velocity and I show that the domain wall can move at a very low propagation field (0.1mT)
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Jenkins, Anne Ceri. "Applications of spin-polarised relativistic scattering theory to the calculation of the electronic properties of heavy metals and alloys." Thesis, Keele University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321408.
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Andrieux, Vincent. "Polarisation of quarks and gluons inside the nucleon." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112244/document.
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Cette thèse présente un travail relatif à l'étude de la structure en spin longitudinal du nucléon. Le but est de déterminer la contribution des constituants du proton, quarks et gluons, à la formation de son spin 1/2. L'analyse s'appuie sur les données de l'expérience COMPASS qui bénéficie d'un faisceau de muons polarisés à 200 GeV diffusé sur les protons polarisés d'une cible d'ammoniac (NH₃) de 1,2 m de long. On mesure l'asymétrie de spin longitudinal des sections efficaces de diffusion profondément inélastique. On extrait la fonction de structure en spin du proton, g₁p, étendant la couverture cinématique mondiale à des régions inexplorées jusqu'à maintenant (0,0036 < x < 0,57; 1,03 < Q² (GeV/c)² < 96 et 23 < W² (GeV/c)² < 320). Les résultats, d'une grande précision statistique, sont inclus dans une analyse des données mondiales de g₁p, g₁d et g₁n (proton, deutéron et neutron) au 2ème ordre de QCD afin de paramétrer les distributions de quarks et de gluons polarisés. L'étendue de la couverture cinématique en x et Q² des données mondiales de g₁, un élément déterminant pour la sensibilité à la polarisation des gluons ΔG, s'avère trop limitée pour constituer une extraction précise de celle-Ci. Néanmoins, l'analyse QCD permet de déterminer la contribution du spin des quarks au spin du proton à 0.26<ΔΣ<0.33 à Q² = 3 (GeV/c)² dans le schéma MSbar. L'étude montre que l'incertitude principale sur ΔΣ est liée au choix des formes fonctionnelles utilisées dans la régression des données. Enfin, la règle de somme de Bjorken, qui constitue un test de QCD, est vérifiée avec une précision de 9% en utilisant les données de COMPASS uniquementThe work presented in this thesis is related to the study of the longitudinal spin structure of the nucleon. The aim is to determine the contribution to the spin 1/2 of the proton in terms of its constituents, quarks and gluons. The analysis is performed on the data taken with the COMPASS experiment, which benefits from a polarised muon beam at 200 GeV scattered off polarised protons from an ammonia target of 1.2 m long. The double longitudinal spin asymmetry of deep inelastic scattering cross-Section. The spin-Dependent structure function of the proton g₁p is derived from these measurements, which extend the kinematic world coverage to unexplored region so far (0,0036 < x< 0,57; 1,03 < Q² (GeV/c)² < 96 and 23 < W² (GeV/c)² < 320).The results obtained with a high statistical precision are included in a Next-To-Leading order QCD analysis of world g₁p, g₁d and g₁n (proton, deuteron and neutron) data to parametrise the polarised quark and gluon distributions. The g₁ world coverage of the x and Q² kinematic domain, which is a key point in the sensitivity to the gluon polarisation ΔG, turns out to be too limited for an accurate ΔG determination. Nevertheless, the QCD analysis allows to determine the quark spin contributions to the proton spin to 0.26<ΔΣ<0.33 at Q² = 3 (GeV/c)² in the MSbar scheme. The dominant uncertainty on ΔΣ is related to the choice of functional forms assumed in the fit. Finally, the Bjorken sum rule, which constitutes a fundamental test of QCD, is verified on the COMPASS data alone with a precision of 9%
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Bowles, Cameron Michael Albert, and cameronbowles@hotmail com. "Pushing the boundaries of condensed matter electron momentum spectroscopy." The Australian National University. Research School of Physical Sciences and Engineering, 2008. http://thesis.anu.edu.au./public/adt-ANU20080409.193948.
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An electron momentum spectrometer at the Australian National University has been used to study various aspects of different solid state systems. EMS is a transmission mode technique and involves the collision of the incident electron with a bound electron, after which both electrons are ejected and measured in coincidence. Through well defined reaction kinematics the complete valence
spectral momentum density A(ɛ,q) can be measured. The spectrometer has been used to measure the spectral momentum
densities (spectral functions) of single crystal targets, as well as targets in disordered states. A new spin polarised electron source was constructed and implemented in the ANU spectrometer, which was used to measure spin dependent features of ferromagnetic samples.¶
This thesis is divided into seven chapters, the first chapter is an introduction into the field of electron momentum spectroscopy, highlighting what has been measured before and how the technique has progressed to its present state. Some comparisons to other experimental techniques will be made.¶
The second chapter describes the ANU EMS spectrometer in detail. The technique requires some technical and advanced equipment that is often used in novel ways. The production of thin (20 nm) free standing targets will be detailed, along with the experimental chamber and electronics used to run the apparatus and collect data. The determination of the energy and momentum resolution of the experiment is also described.¶
The third chapter will detail the design and construction of the new spin polarised electron source. The results of commissioning and characterizing the new source will be presented.¶
Chapters four through six will present the measured results. The fourth chapter will detail the single crystalline measurements for the group eleven noble metals (Cu, Ag and Au). Each sample was measured along three high symmetry directions and compared to a DFT calculation using the LDA and a FP-LMTO basis. The fifth chapter will include the results from samples that were in disordered states, a measurement which is unique to the EMS technique. The polycrystalline and amorphous states of the Si and Ge semiconductors are presented and conclusions are made to the degree of difference in the results and to which theoretical approach to the unique amorphous state of the semiconductors best matches the EMS results. The sixth chapter includes results of ferromagnetic iron, measured using the spin polarised electron source. The spectrometer was used to measure spin-polarised electron-energy-loss-spectroscopy (SPEELS) and magnetic electron-Compton profiles. A theoretical investigation is also presented in chapter six which details the advancements required in the spin polarised electron gun to measure an accurate spin-polarised EMS spectra of a ferromagnetic Fe sample.¶
Chapter 7 includes the summary of all the results presented and conclusions reached from the comparison of the measured EMS spectra and various theoretical calculations. A discussion is presented about the future directions and possibilities of the EMS technique.
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Ray, Soumya Jyoti. "Nanoscale investigation of superconductivity and magnetism using neutrons and muons." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3190.
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The work presented in this thesis was broadly focussed on the investigation of the magnetic behaviour of different superconducting materials in the form of bulk (singe crystals and pellets) and thin films (nanomagnetic devices like superconducting spin valves etc). Neutrons and muons were extensively used to probe the structural and magnetic behaviour of these systems at the nanoscale along with bulk characterisation techniques like high-sensitive magnetic property measurements, scanning probe microscopy and magneto-transport measurements etc. The nanoscale interplay of Superconductivity and Ferromagnetism was studied in the thin film structures using a combination of Polarised Neutron Reflectivity (PNR) and Low Energy Muon Spin Rotation (LE-µSR) techniques while bulk Muon Spin Rotation (µSR) technique was used for microscopic magnetic investigation in the bulk materials. In the Fe/Pb heterostructure, evidence of the Proximity Effect was observed in the form of an enhancement of the superconducting penetration depth (λs) with an increase in the ferromagnetic layer thickness (dF) in both the bilayered and the trilayered structures. The existence of an Inverted Magnetic Region was also detected at the Ferromagnet-Superconductor (F/S) interface in the normal state possibly originating from the induced spin polarisation within the Pb layer in the presence of the neighbouring Fe layer(s). The spatial size (height and width) of the Inverted Magnetic Region did not change much while cooling the sample below the superconducting transition temperature(Tc)and it also stayed unaffected by an increase in the Fe layer thickness and by a change of the applied magnetic field. In the superconducting spin valve structure containing Permalloy (Py) as ferromagnetic layer and Nb as the superconducting layer, LE-µSR measurements revealed the evidence of the decay of magnetic flux density (as a function of thickness) within the Nb layer symmetrically from the Py/Nb interfaces towards the centre of the Nb layer in the normal state. The thickness dependent magnetisation decay occurred over two characteristic length scales in the normal state that stayed of similar values in the superconducting state also. In the superconducting state, an additional contribution towards the magnetisation was found in the vicinity of the Py/Nb interfaces possibly originating from the spin polarisation of the singlet Cooper pairs in these areas. The nanoscale magnetic investigation on a highly engineered F/S/F structure (where each of the F blocks made of multiple Co/Pd layers with magnetic moments aligned perpendicular to the plane of these layers and neighbouring magnetic blocks separated by Ru layers giving rise to antiferromagnetic alignment) using LE-µSR showed an antisymmetric thickness dependent magnetic flux density profile with two characteristic length scales. In the superconducting state, the magnetic flux density profile got modified within the superconducting Nb₆₇Ti₃₃ layer near the F/S interfaces in a way similar to that of observed in the case of Py/Nb system, most likely because of the spin polarisation of the superconducting electron pairs. The vortex magnetic phase diagram of Bi₂Sr₂Ca₂Cu₃O10-δ was studied using the Muon Spin Rotation (µSR) technique to explore the effects of vortex lattice melting and rearrangements for vortex transitions and crossover as a function of magnetic field and temperatures. At low magnetic fields, the flux vortices undergo a first order melting transition from a vortex lattice to a vortex liquid state with increasing temperature while another transition also occurred with increasing field at fixed temperature to a vortex glass phase at the lowest temperatures. Evidence of a frozen liquid phase was found in the intermediate field region at low temperature in the form of a lagoon in the superconducting vortex state which is in agreement with earlier observations made in BiSCCO-2212. The magnetic behaviour of the unconventional superconductor Sr₂RuO₄ was investigated using µSR to find the evidence of normal state magnetism and the nature of the vortex state. In the normal state, a weak hysteretic magnetic signal was detected over a wide temperature and field range believed to be supporting the evidence of a chiral order parameter. The nature of the vortex lattice structure was obtained in different parts of the magnetic phase diagram and the evidence of magnetic field driven transition in the lattice structure was detected from a Triangular→Square structure while the vortex lattice stayed Triangular over the entire temperature region below Tc at low fields with a disappearance of pinning at higher temperatures.
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Belkhir, 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.
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Un calcul de bandes spin polarisé basé sur une méthode de fonctions localisées a été effectué sur MnO et NiO dans leur configuration antiferromagnétique. Lorsque l'échange intra-atomique est assez fort comme dans MnO, il apparaît une bande interdite entre les bandes d majoritaires et minoritaires qui suffit à expliquer les propriétés isolantes de cet oxyde. De plus nous avons montré qu'il existe une séparation systématique à l'intérieur de chaque bande majoritaire et minoritaire due essentiellement à la structure D5(3d). La présence d'une telle bande minoritaire interdite dans le NiO est responsable de ses propriétés semiconductrices. Ainsi l'hybridation p-d qui empêchait la formation d'une bande interdite dans la structure NaCl, conduit à une issue favorable lorsqu'on prend en compte l'arrangement magnétiqueA 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
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Ding, Haifeng. "Spin-polarized scanning tunneling microscopy." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963217186.
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Hasch, Delia. "Messung der polarisierten Strukturfunktion g1(x, Q 2) des Protons mit dem HERMES-Experiment." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 1999. http://dx.doi.org/10.18452/14523.
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Die vorliegende Arbeit beschreibt die Messung der polarisierten Strukturfunktion g1p des Protons in der polarisationsabh"angigen tief inelastischen Positron-Proton-Streuung bei einer Schwerpunktenergie von 7.5 GeV. Die Analyse umfasst die 1997 mit dem Hermes-Experiment am Hera-Positronring aufgezeichneten Daten der Streuung polarisierter Positronen der Energie 27.6 GeV an einem polarisierten Wasserstofftarget. Aus den Z"ahlraten der inklusiv nachgewiesenen, selektierten Positronen f"ur die parallele und die antiparallele Ausrichtung der Spinvektoren von Strahlteilchen und Targetatomen wurde die Streuquerschnitts- Asymmetrie der Positron-Proton-Streuung bestimmt. In verschiedenen Korrekturverfahren wurden Untergrundprozesse, Spektrometereinfl"usse sowie Strahlungskorrekturen ber"ucksichtigt. Die Untergrundkorrekturen wurden aus den Daten, die Spektrometerkorrekturen aus einer Monte-Carlo- Simulation ermittelt. Die Abh"angigkeit der Monte-Carlo- und Strahlungskorrekturen von der gew"ahlten Modell-Asymmetrie zur Beschreibung der polarisationsabh"angigen Effekte wurde durch die Anwendung eines iterativen Verfahrens minimiert. Aus der vollst"andig korrigierten Streuquerschnitts-Asymmetrie wurde die Asymmetrie g1/F1 im kinematischen Bereich 0.021 < x < 0.85 und Q2 > 0.8 GeV^2 mit einer systematischen Unsicherheit von etwa 8% bei einer statistischen Genauigkeit von 6% bis 20%, ansteigend f"ur abnehmende x-Werte, bestimmt. Die aus g1/F1 berechnete polarisierte Strukturfunktion g1p(x,Q2) wird, unter der Annahme einer von q2 unabh"angigen Asymmetry g1/F1, zu einem festen Wert Q2_0 entwickelt. Ihr erstes Moment im gemessenen x-Bereich betr"agt int_{0.021}^{0.85} dx g1p(x,Q2_0) = 0.122 =- 0.003 (stat) =- 0.010 (sys) at Q2_0 = 2.5 GeV^2. Der Vergleich mit den Werten des SMC-Experimentes am CERN und des E143-Experimentes am SLAC f"ur das erste Moment von g1p wurde unter Anwendung des gleichen Integrationsschemas f"ur den jeweils gemeinsam gemessenen x-Bereich sowie f"ur gleiche Q2_0 Werte durchgef"uhrt. Das Ergebnis der vorliegenden Analyse befindet sich, bezogen auf die statistische Genauigkeit der Messungen, in "Ubereinstimmung innerhalb von 0.6 bzw. 1.2 Standardabweichungen mit den Resultaten des E143- bzw. SMC-Experimentes. Durch Extrapolation der Strukturfunktion auf den gesamten x-Bereich [0,1] wird das erste Moment zu \int_{0}^{1} dx g1p(x,Q2_0) = 0.132 +- 0.003 (stat) +- 0.010 (sys) +- 0.006 (extr) bestimmt, wobei der zus"atzliche Fehler die Unsicherheit in der Extrapolation x -> 0 wiedergibt. Die Interpretation der vorliegenden Messung im Rahmen des Quark-Parton-Modells unter Ber"ucksichtigung von QCD-Korrekturen der Ordnung O(alphaS^3) ergibt einen Beitrag der Quarks zum Gesamtspin des Nukleons von (30 +- 10)% f"ur Q2_0 = 2.5 GeV^2. Dieses Ergebnis entspricht einer Abweichung von der Ellis-Jaffe-Vorhersage um 2.5 Standardabweichungen, bezogen auf den angegebenen Gesamtfehler, und f"uhrt im Kontext des Quark-Parton-Modells zur Interpretation negativ polarisierter Strange-Seequarks mit einem Beitrag von (-9 +- 4)% f"ur Q2_0 = 2.5 GeV^2. Von verschiedenen Gruppen werden aus QCD-Analysen unterschiedlicher Datens"atze Beitr"age der Quarks zum Nukleonspin von 19% bis 44% angegeben. Unter Hinzunahme der Hermes-Messung der polarisierten Neutronstrukturfunktion g1n wurde der Wert der fundamentalen Bjorken-Summenregel f"ur Q2_0 = 2.5 GeV^2 bestimmt. Dieser Wert befindet sich, bei einer auf den Gesamtfehler bezogenen Genauigkeit von 13%, innerhalb von 0.5 Standardabweichungen in "Ubereinstimmung mit der theoretischen Vorhersage, berechnet unter Ber"ucksichtigung von QCD-Korrekturen der Ordnung O(\alphaS^3).The subject of this thesis is the measurement of the polarised structure function g1p of the proton in deeply inelastic positron-proton-scattering at a centre of mass energy of 7.5 GeV. The data used in the analysis were recorded during the 1997 running period of the Hermes experiment using a longitudinally nuclear polarised hydrogen target in the 27.6 GeV Hera polarised positron storage ring. The cross section asymmetry of positron-proton-scattering has been measured by counting the number of inclusively reconstructed and selected positrons with target spin vector parallel or antiparallel to the beam spin direction. Background processes, spectrometer effects, and radiative corrections have been taken into account by applying different correction procedures. Here background corrections were determined from data while spectrometer corrections were computed from Monte Carlo simulation. The dependence of Monte Carlo and radiative corrections on the model asymmetry chosen to describe polarisation dependent effects has been minimised by applying an iterative procedure. From the fully corrected cross section asymmetry the asymmetry g1/F1 has been computed in the kinematic region 0.021 < x < 0.85 and Q2 > 0.8 GeV^2 with a systematic uncertainty of 8% and a statistical accuracy of 6% to 20%, raising for decreasing x values. The polarised structure function g1p(x,Q2), determined from the asymmetry g1/F1 , was evoluted to a common Q2_0 value assuming g1/F1 to be independent of Q2. Its first moment evaluated in the measured x region is int_{0.021}^{0.85} dx g1p(x,Q2_0) = 0.122 =- 0.003 (stat) =- 0.010 (sys) at Q2_0 = 2.5 GeV^2. This result has been compared with those from E143 at SLAC and from SMC at CERN, both calculated with the same integration scheme and for the kinematic range of Hermes. With respect to the statistical uncertainties the agreement is better than 0.6 and 1.2 standard deviations, respectively. Extrapolation over the entire x range [0,1] yield for the first moment\int_{0}^{1} dx g1p(x,Q2_0) = 0.132 +- 0.003 (stat) +- 0.010 (sys) +- 0.006 (extr) where the additional error gives the uncertainty in the extrapolation x -> 0. The interpretation of this measurement in the framework of the quark parton model taking QCD corrections of the order O(alphaS^3) into account results in a contribution of the quarks to the total nucleon spin of (30 +- 10)% at Q2_0 = 2.5 GeV^2. This result corresponds to a deviation from the Ellis-Jaffe prediction by 2.5 standard deviation regarding the given total uncertainty. Within the quark parton model the deviation can be interpreted as negative polarisation of the strange sea quarks with a contribution of (-9 +- 4)% at Q2_0 = 2.5 GeV^2. Different groups give contributions of the quarks to the nucleon spin of 19% to 44% which were obtained from QCD analyses of various data sets. The fundamental Bjorken sum rule has been determined at Q2_0 = 2.5 GeV^2 using the Hermes measurement of the polarised neutron structure function g1n. With respect to the experimental accuracy of 13 %, the result agrees within 0.5 standard deviation with the theoretical prediction taking QCD corrections of the order O(alphaS^3) into account.
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Tehrani-Nasab, Sa'id. "On spin diffusion in polarized paramagnets." Thesis, Royal Holloway, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391900.
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Pramanik, Sandipan. "Spin Polarized Transport in Nanoscale Devices." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1092.
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The ultimate goal in the rapidly burgeoning field of spintronics is to realize semiconductor-based devices that utilize the spin degree of freedom of a single charge carrier (electron or hole) or an ensemble of such carriers to achieve novel and/or enhanced device functionalities such as spin based light emitting devices, spin transistors and femto-Tesla magnetic field sensors. These devices share a common feature: they all rely on controlled transport of spins in semiconductors. A prototypical spintronic device has a transistor-like configuration in which a semiconducting channel is sandwiched between two contacts (source and drain) with a gate electrode sitting on top of the channel. Unlike conventional charge-based transistors, the source electrode of a spin transistor is a ferromagnetic (or half-metallic) material which injects spin polarized electrons in the channel. During transit, the spin polarizations of the electrons are controllably rotated by a gate electric field mediated spin-orbit coupling effect. The drain contact is ferromagnetic (or half-metallic) as well and the transmission probability of an electron through this drain electrode depends on the relative orientation of electron spin polarization and the (fixed) magnetization of the drain. When the spins of the electrons are parallel to the drain magnetization, they are transmitted by the drain resulting in a large device current (ON state of spin FET). However, these electrons will be completely blocked if their spins are antiparallel to the drain magnetization, and ideally, in this situation device current will be zero (OFF state of spinFET). Thus, if we vary the gate voltage, we can modulate the channel current by controlling the spin orientations of the electrons with respect to the drain magnetization. This is how transistor action is realized (Datta-Das model). However, during transport, electrons' velocities change randomly with time due to scattering and hence different electrons experience different spin-orbit magnetic fields. As a result, even though all electrons start their journey with identical spin orientations, soon after injection spins of different electrons point along different directions in space. This randomization of initial spin polarization is referred to as spin relaxation and this is detrimental to the spintronic devices. In particular, for Datta-Das transistor, this will lead to inefficient gate control and large leakage current in the OFF state of the spinFET. The aim of this work is to understand various spin relaxation processes that are operative in semiconductor nanostructures and to indicate possible ways of minimizing them. The theoretical aspect of this work (Chapters 2-5) focuses on the D'yakonov-Perel' process of spin relaxation in a semiconductor quantum wire. This process of spin relaxation occurs because during transport electron spin precesses like a spinning top about the spin-orbit magnetic field. We show that the conventional drift-diffusion model of spin transport, which has been used extensively in literature, completely breaks down in case of a quantum confined system (e.g. a quantum wire). Our approach employs a semi-classical model which couples the spin density matrix evolution with the Boltzmann transport equation. Using this model we have thoroughly studied spin relaxation in a semiconductor quantum wire and identified several inconsistencies of the drift-diffusion formalism.The experimental side of this work (Chapters 6-8) deals with two different issues: (a) performing spin transport experiments in order to extract spin relaxation length and time in various materials (e.g. Cu, Alq3) under one-dimensional confinement, and (b) measurement of the ensemble spin dephasing time in self-assembled cadmium sulfide quantum dots using electron spin resonance technique. The spin transport experiment, as described in Chapter 7 of this dissertation, shows that the spin relaxation time in organic semiconductor (Alq3) is extremely long, approaching a few seconds at low temperatures. Alq3 is the chemical formula of tris- 8 hydroxy-quinoline aluminum, which is a small molecular weight organic semiconductor. This material is extensively used in organic display industry as the electron transport and emission layer in green organic light emitting diodes. The long spin relaxation time in Alq3 makes it an ideal platform for spintronics. This also indicates that it may be possible to realize spin based organic light emitting diodes which will have much higher internal quantum efficiency than their conventional non-spin counterparts. From spin transport experiments mentioned above we have also identified Elliott-Yafet mode as the dominant spin relaxation mechanism operative in organic semiconductors. Electron spin resonance experiment performed on self-assembled quantum dots (Chapter 8) allows us to determine the ensemble spin dephasing time (or transverse spin relaxation time) of electrons confined in these systems. In quantum dots electrons are strongly localized in space. Surprisingly, the ensemble spin dephasing time shows an increasing trend as we increase temperature. The most likely explanation for this phenomenon is that spin dephasing in quantum dots (unlike quantum wells and wires) is dominated by nuclear hyperfine interaction, which weakens progressively with temperature. We hope that our work, which elaborates on all of the above mentioned topics in great detail, will be a significant contribution towards the current state of knowledge of subtle spin-based issues operative in nanoscale device structures, and will ultimately lead to realization of novel nano-spintronic devices.
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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.
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It has been recently established that spin-polarized current can have a direct influence on the magnetization dynamics in conducting ferromagnets. This effect has quantum origin and is of great interest from both fundamental and applied viewpoints. In particular, it can be useful for developing magnetoresistance random access memory, magnetic logic elements and microwave devices, to name a few.
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Bhandari, Nikhil K. "Tunable All Electric Spin Polarizer." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1393237571.
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Chen, Peifeng. "Spin polarized tunneling and spin injection in Fe-GaAs hybrid structures." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=981364837.
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Gröbli, Jean-Claude. "Spin filter and highly polarized electron sources /." [S.l.] : [s.n.], 1995. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11148.
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Newman, Chris. "Spin polarized transport in hybrid ferromagnetic nanostructures." Thesis, Lancaster University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414891.
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Hatton, D. C. "Spin polarized electron scattering at ferromagnetic interfaces." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603854.
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Özdemir, Mehtap Özyüzer Lütfi. "Spin polarized tunneling spectroscopy of intercalated Bi2Sr2CaCu2O8+." [s.l.]: [s.n.], 2006. http://library.iyte.edu.tr/tezlerengelli/master/malzemebilimivemuh/T000557.pdf.
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Fördös, Tibor. "Coherent light sources with spin-polarized current." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLX043/document.
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Les spin-lasers sont des dispositifs semi-conducteurs dans lesquels les processus de recombinaison radiative impliquant des porteurs polarisés en spin résultent en une émission de photons polarisés circulairement. Néanmoins, des anisotropies linéaires supplémentaires dans la cavité conduisent généralement à une émission laser préférentiellement polarisée linéairement et à un éventuel couplage entre modes. Dans cette thèse, une méthode générale pour la modélisation de lasers à semi-conducteurs tels que laser à surface verticale (externe) à cavité et contenant des puits quantiques multiples et impliquant des anisotropies pouvant révéler (i) une biréfringence linéaire locale due au champ de déformation à la surface ou (ii) une biréfringence dans les puits quantiques due au couplage d'amplitude de phase provenant de la réduction du D2d biaxial au groupe de symétrie C2v aux interfaces semiconductrices ternaires III-V. Une nouvelle méthode récursive à matrice S de diffusion est mise en œuvre en utilisant un tenseur de gain dérivé analytiquement des équations de Maxwell-Bloch. Il permet de modéliser les propriétés de l'émission (seuil, polarisation, dédoublement de mode) du laser avec plusieurs zones actives à puits quantiques en recherchant les modes propres résonnants de la cavité. La méthode est démontrée sur des structures laser réelles et est utilisée pour l'extraction de tenseurs de permittivité optique de déformation de surface et de puits quantiques en accord avec des expériences. La méthode est généralisée pour trouver les modes propres au laser dans le cas le plus général des pompes polarisées circulaires (déséquilibre entre les canaux de spin-up et de spin-down) et le dichroïsme à gain linéaire. De plus, la mesure de la matrice de Mueller 4x4 complète pour des angles d'incidence multiples et des angles azimutaux dans le plan a été utilisée pour l'extraction de tenseurs de permittivité optique de couches contraintes superficielles et de puits quantiques. Une telle dépendance spectrale des éléments tensoriels optiques est cruciale pour la modélisation des modes propres du laser de spin, les conditions de résonance, et aussi pour la compréhension des sources d'anisotropies de structureSpin-lasers are semiconductor devices in which the radiative recombination processes involving spin-polarized carriers result in an emission of circularly polarized photons. Nevertheless, additional linear in-plane anisotropies in the cavity generally lead in preferential linearly-polarized laser emission and to possible coupling between modes. In this thesis, a general method for the modeling of semiconductor laser such as vertical-(external)-cavity surface-emitting laser containing multiple quantum wells and involving anisotropies that may reveal i) a local linear birefringence due to the strain field at the surface or ii) a birefringence in quantum wells (QWs) due to phase amplitude coupling originating from the reduction of the biaxial D2d to the C2v symmetry group at the III-V ternary semiconductor interfaces. A novel scattering S-matrix recursive method is implemented using a gain tensor derived analytically from the Maxwell-Bloch equations. It enables to model the properties of the emission (threshold, polarization, mode splitting) from the laser with multiple quantum well active zones by searching for the resonant eigenmodes of the cavity. The method is demonstrated on real laser structures and is used for the extraction of optical permittivity tensors of surface strain and quantum wells in agreement with experiments. The method is generalized to find the laser eigenmodes in the most general case of circular polarized pumps (unbalance between the spin-up and spin-down channels) and linear gain dichroism. In addition, the measurement of full 4x4 Mueller matrix for multiple angles of incidence and in-plane azimuthal angles has been used for extraction of optical permittivity tensors of surface strained layers and quantum wells. Such spectral dependence of optical tensor elements are crucial for modeling of spin-laser eigenmodes, resonance conditions, and also for understanding of sources of structure anisotropies
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Luther, Bryan A. "Spin observables in the quasifree (polarized proton, polarized neutron) reaction at 495 MeV /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487848078451672.
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Dörr, Kathrin. "Ferromagnetic manganites: spin-polarized conduction and competing interactions." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1193676987929-14995.
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Electronic properties of solids are vitally important for modern technology, one may think of microelectronics, magnetic data storage, communication technologies and others. Sometimes, it seems possible to postpone the step of fundamental understanding when starting the application of a new material. However, lasting success and discovery of principally new approaches is based on it ...
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Taddei, Fabio. "Spin-polarized transport in superconducting and ferromagnetic nanostructures." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369499.
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Hayward, D. J. "Experiments on magnetically spin-polarized '3He-'4He solutions." Thesis, Lancaster University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379199.
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Dörr, Kathrin. "Ferromagnetic manganites: spin-polarized conduction and competing interactions." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A23959.
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Electronic properties of solids are vitally important for modern technology, one may think of microelectronics, magnetic data storage, communication technologies and others. Sometimes, it seems possible to postpone the step of fundamental understanding when starting the application of a new material. However, lasting success and discovery of principally new approaches is based on it ...
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Yokoyama, Koji. "Muon probes of spin-polarized electrons in GaAs." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=104&did=1907186881&SrchMode=1&sid=1&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270484411&clientId=48051.
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Thesis (Ph. D.)--University of California, Riverside, 2009.Includes abstract. Includes bibliographical references (leaves 121-123). Issued in print and online. Available via ProQuest Digital Dissertations.