Tesis sobre el tema "Experimental condensed matter physics"
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Daniilidis, Nikolaos. "Experimental studies of the Bragg Glass transition in niobium". View abstract/electronic edition; access limited to Brown University users, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3318303.
Texto completoVarner, Samuel John. "Experimental and computational techniques in carbon-13 NMR". W&M ScholarWorks, 1999. https://scholarworks.wm.edu/etd/1539623952.
Texto completoXu, Yan 1963 Jan 31. "Experimental study of the structure of Ni-Zr metallic glasses". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41212.
Texto completoGiomi, Luca. "Unordinary order a theoretical, computational and experimental investigation of crystalline order in curved space /". Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2009. http://wwwlib.umi.com/cr/syr/main.
Texto completoKremeyer, Kevin P. 1968. "Experimental and computational investigations of binary solidification". Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/289267.
Texto completoDhaubhadel, Rajan. "An experimental study of dense aerosol aggregations". Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/663.
Texto completoBaggioli, Matteo. "Gravity, holography and applications to condensed matter". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/395205.
Texto completoStrongly coupled physical systems along with their corresponding, and usually exotic, features are elusive and not suitable to be described by conventional and perturbative approaches, which in those cases are not able to provide a controllable and robust tool for computations. Nevertheless non perturbative effects and strongly correlated frameworks are ubiquitous in nature, expecially in Condensed Matter physics. The AdS/CFT correspondence, born from the excitement of ideas and efforts employed in finding out a possible description of Quantum Gravity, lead to a flurry of fresh air into the subject, introducing an unexpected and brandnew perspective for dealing with strongly coupled field theories. In its more general formulation, known as Gauge-Gravity duality, this setup accounts for an effective and efficient weapon to tackle those kind of problems using a dual gravitational description which turns out to be way easier than the original one. In the last years, a huge number of developments have been achieved in applying the duality towards modern and hot condensed matter misteries, such as the Strange Metals nature or the mechanism underlying the High-Tc Superconductivity.\\ Momentum relaxation is an ever-present and unavoidable ingredient of any realistic Condensed Matter system. In real-world materials the presence of a lattice, impurities or disorder forces momentum to dissipate and leads to relevant physical effects such as the finiteness of the DC transport properties, i.e. conductivities. Several open questions are connected to those quantities expecially in the limit of strong momentum relaxation where novel insulating states appear and unexpected quantum phase transitions between the latter and metallic states (MIT) arise.\\[0.2cm] The main purpose of this thesis is the introduction of momentum dissipation and its consequent effects into the framework of AdS/CMT, namely the applications of the Gauge-Gravity duality to Condensed Matter. \\ A convenient and effective way of breaking translational symmetry of the the dual quantum field theory is provided by Massive Gravity (MG) theories, which constitues a tractable and easy tool to adress several interesting questions in strongly coupled systems with momentum dissipation. Born to solve cosmological puzzles, MG can now be reconsidered under a completely new perspective and could become a useful framework for ''Real-world" phenomena and "low energy" applications. We consider generic massive gravity models embedded into asymptotically Anti de Sitter spacetime and we analyze them using holographic techniques.
Hamida, Youcef. "MAGNETISM IN A NUMBER OF METAL ORGANIC FRAMEWORKS (MOFs) WITH 1D AND 3D CHARACTERISTICS: AN EXPERIMENTAL AND ANALYTICAL STUDY". Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/195069.
Texto completoPh.D.
Metal Organic Frameworks (MOFs) exhibit many excellent physical properties including magnetic properties for potential applications in devices. More importantly for the subject of this thesis, MOFs are ideal for the realization of low dimensional magnetism because of the large selection of ligands connecting magnetic centers in making the framework. The materials studied in this thesis include ten magnetic MOFs of the form M(L1)(L2) [M = Cu, Ni, Co, Fe, Mn; L1 = NDC, bpdc, BDC, BODC, N3; L2 = DMF, H2O, TED, bpy]. Polycrystalline powder samples as well as single crystal samples were synthesized. Their crystal structures were determined, and their magnetic and thermodynamic properties were measured and analyzed. Eight of these materials were characterized as 1D magnets and two as 3D magnets. In the 1D case it is found that above Tm [the temperature at which the magnetic susceptibility χ(T) has a peak] the magnetic behavior of MOFs (S ≥ 1) can be well described with the Classical Fisher Model (CFM). Near and below TC the spins take a more definite orientation than allowed for in the CFM and hence the Ising Model (IM) was used for fitting. Both CFM and IM yield fairly consistent intrachain couplings (J) when applied in their appropriate temperature region. To estimate the interchain exchange (J′), the susceptibility for a magnetic chain in the mean field of neighboring chains is used. In all cases, as expected, the ratio of J to J′ was less than 10%. The special case of Cu(N3)2bpy (S = ½) was analyzed with the spin ½ IM. Although the specific heat data (Ctotal) for most of the 1D MOFs showed no clear phase transition, a low temperature fit to the electron-phonon specific heats yielded apparent heavy fermion-like &gamma values on the order of several hundred mJ/mol K2. The lattice specific heat (C lattice) was estimated using a Debye-Einstein hybrid model. Subtracting Clattice from Ctotal, magnetic specific heat (CM) with a broad peak characteristic of low dimensional magnetism was obtained. The peak in CM was at temperature near that expected from χ(T) fits. The J values obtained from the magnetic specific heat fits were in good agreement with those obtained from χ(T) fits. Once the magnetic specific heat was accounted for, γtakes values in the expected range of few mJ/mol K2. For 3D MOFs [Mn(N3)2bpy and Fe(N3)2bpy], the existence of long range canted antiferromagnetic ordering was observed in both magnetic and specific heat measurements with phase transitions at 38 K and 20 K in the case of Mn(N3)2bpy and Fe(N3)2bpy, respectively. These transition temperatures are considered fairly high for molecular based materials. In both Mn(N3)2bpy and Fe(N3)2bpy, the χ(T) data fit well to the Heisenberg model for a diamond-type network. The transition can clearly be seen with an abrupt increase in the magnetization below TC and a shift to a higher temperature in the specific heat when measured under an applied magnetic field. The systematic approach in this work led to the successful estimate of C lattice resulting in meaningful fitting of χ(T) and Cmagnetic to the appropriate theoretical models in magnetism. It also led the discovery of ferrimagnets or canted antiferromagnets M(N3)2bpy with large coercivity and rather high transition temperature. The results of this study have been published in three articles in the Journal of Applied physics, and two manuscripts are under preparation for submission [1-5].
Temple University--Theses
KIM, Eui-Jong. "Development of numerical models of vertical ground heat exchangers and experimental verification : domain decomposition and state model reduction approach". Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00684138.
Texto completoHinton, Michael J. "Superfluidity in Ultrathin Cuprates and Niobium/Ferromagnetic Heterostructures". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1420673882.
Texto completoAndersson, Mikael Svante. "Interacting Magnetic Nanosystems : An Experimental Study Of Superspin Glasses". Doctoral thesis, Uppsala universitet, Fasta tillståndets fysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-319717.
Texto completoNawarange, Amruta V. "Optical Emission Spectroscopy during Sputter Deposition of CdTe Solar Cells and CuTe-Based Back Contacts". University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1321656598.
Texto completoStepanov, Petr. "Spin and Charge Transport in Monolayer and Trilayer Graphene in the Quantum Hall Regime". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1532103607994675.
Texto completoTriana, Carlos A. "Atomic short-range order, optical and electronic properties of amorphous transition metal oxides : An experimental and theoretical study of amorphous titanium aTiO2 and tungsten aWO3 solid thin-film oxides". Doctoral thesis, Uppsala universitet, Fasta tillståndets fysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-318193.
Texto completoWolfe, Christopher Stuart. "Novel Techniques for Detection and Imaging of Spin Related Phenomena: Towards Sub-Diffraction Limited Resolution". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437316315.
Texto completoQiu, Lei. "Exploring 2D Metal-Insulator Transition in p-GaAs Quantum Well with High rs". Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1386337954.
Texto completoMroz, Michael V. "Characterization of Morphological and Chemical Properties of Scandium Containing Cathode Materials". Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou158470102410177.
Texto completoPaul, Sanjoy. "CHARGE TRANSPORT IN LIQUID CRYSTALLINE SMECTIC AND DISCOTIC ORGANIC SEMICONDUCTORS: NEW RESULTS AND EXPERIMENTAL METHODOLOGIES". Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1469836810.
Texto completoSaers, Robert. "Ultracold rubidium atoms in periodic potentials". Doctoral thesis, Umeå universitet, Fysik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1821.
Texto completoXu, Jinsong. "Electronic and Spin Dependent Phenomena in Two-Dimensional Materials and Heterostructures". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531925662989238.
Texto completoMichel, Amelie. "Etude du comportement des gaz de fission dans le dioxyde d'uranium : mécanismes de diffusion, nucléation et grossissement de bulles". Phd thesis, Université de Caen, 2011. http://tel.archives-ouvertes.fr/tel-00691286.
Texto completoTayade, Renuka. "Theoretical and experimental contribution to the study of exchange-spring magnets". Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2014. http://tel.archives-ouvertes.fr/tel-01062741.
Texto completoBorshch, Volodymyr. "Nanosecond Electric Modification of Order Parameters". Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1416443341.
Texto completoPesquera, Herrero David. "Strain and interface-induced charge, orbital and spin orderings in transition-me tal oxide perovskites". Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/283932.
Texto completoCourtois, Hervé. "Supraconductivité de proximité dans les nanostructures métalliques artificielles". Phd thesis, Université Joseph Fourier (Grenoble), 1994. http://tel.archives-ouvertes.fr/tel-00116792.
Texto completoChevalier, Alexis. "ETUDE EXPERIMENTALE, ELABORATION ET MODELISATION DE MATERIAUX COMPOSITES A BASE DE POUDRES MAGNETIQUES DOUCES". Phd thesis, Université de Bretagne occidentale - Brest, 1998. http://tel.archives-ouvertes.fr/tel-00484041.
Texto completoBARBERET, Philippe. "Développement d'une ligne d'irradiation microfaisceau en mode ion par ion pour la radiobiologie expérimentale à l'échelle cellulaire". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2003. http://tel.archives-ouvertes.fr/tel-00004084.
Texto completoBhallamudi, Vidya Praveen. "Spins in heterogeneous landscapes: Consequences for transport and imaging". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306871981.
Texto completoSkorobogatiy, Maksim 1974. "Numerical methods in condensed matter physics". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/82756.
Texto completoIncludes bibliographical references (leaves 62-63).
by Maksim A. Skorobogatiy.
M.Eng.
Wang, Ruizhe. "Magnetic fluctuations and clusters in the itinerant ferromagnet Ni-V close to a disordered quantum critical point". Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1555936445433091.
Texto completoClifford, Dustin M. "Non-Conventional Approaches to Syntheses of Ferromagnetic Nanomaterials". VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4205.
Texto completoZhao, Hongming. "ETUDE EXPERIMENTALE DE LA PROPRIETE DE COUPLAGE SPIN-ORBITE DANS DES STRUCTURES SEMI-CONDUCTRICES DE BASSE DIMENSIONALITE". Phd thesis, Université de Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00595906.
Texto completoMoussavi-Madani, Mahmoud. "Positron interactions in condensed matter". Thesis, Royal Holloway, University of London, 1987. http://repository.royalholloway.ac.uk/items/78c4cb98-6511-4083-8827-9172a34368aa/1/.
Texto completoMorris, Andrew James. "A stochastic approach to condensed matter physics". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608498.
Texto completoGentle, Simon Adam. "Holography, black holes and condensed matter physics". Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7286/.
Texto completoYang, Xu. "Symmetry and topology in condensed matter physics:". Thesis, Boston College, 2021. http://hdl.handle.net/2345/bc-ir:109160.
Texto completoRecently there has been a surging interest in the topological phases of matter, including the symmetry-protected topological phases, symmetry-enriched topological phases, and topological semimetals. This thesis is aiming at finding new ways of searching and probing these topological phases of matter in order to deepen our understanding of them. The body of the thesis consists of three parts. In the first part, we study the search of filling-enforced topological phases of matter in materials. It shows the existence of symmetry-protected topological phases enforced by special electron fillings or fractional spin per unit-cell. This is an extension of the famous Lieb-Schultz-Mattis theorem. The original LSM theorem states that the symmetric gapped ground state of the system must exhibit topological order when there's fractional spin or fractional electron filling per unit-cell. However, the LSM theorem can be circumvented when commensurate magnetic flux is present in the system, which enlarge the unit-cells to accommodate integer numbers of electrons. We utilize this point to prove that the ground state of the system must be a symmetry-protected topological phase when magnetic translation symmetry is satisfied, which we coin the name “generalized LSM theorem”. The theorem is proved using two different methods. The first proof is to use the tensor network representation of the ground state wave-function. The second proof consists of a physical argument based on the idea of entanglement pumping. As a byproduct of this theorem, a large class of decorated quantum dimer models are introduced, which satisfy the condition of the generalized LSM theorem and exhibit SPT phases as their ground states. In part II, we switch to the nonlinear response study of Weyl semimetals. Weyl semimetals (WSM) have been discovered in time-reversal symmetric materials, featuring monopoles of Berry’s curvature in momentum space. WSM have been distinguished between Type-I and II where the velocity tilting of the cone in the later ensures a finite area Fermi surface.To date it has not been clear whether the two types results in any qualitatively new phenomena. In this part we focus on the shift-current response ($\sigma_{shift}(\omega)$), a second order optical effect generating photocurrents. We find that up to an order unity constant, $\sigma_{shift}(\omega)\sim \frac{e^3}{h^2}\frac{1}{\omega}$ in Type-II WSM, diverging in the low frequency $\omega\rightarrow 0$ limit. This is in stark contrast to the vanishing behavior ($\sigma_{shift}(\omega)\propto \omega$) in Type-I WSM. In addition, in both Type-I and Type-II WSM, a nonzero chemical potential $\mu$ relative to nodes leads to a large peak of shift-current response with a width $\sim |\mu|/\hbar$ and a height $\sim \frac{e^3}{h}\frac{1}{|\mu|}$, the latter diverging in the low doping limit. We show that the origin of these divergences is the singular Berry’s connections and the Pauli-blocking mechanism. Similar results hold for the real part of the second harmonic generation, a closely related nonlinear optical response. In part III, we propose a new kind of thermo-optical experiment: the nonreciprocal directional dichroism induced by a temperature gradient. The nonreciprocal directional dichroism effect, which measures the difference in the optical absorption coefficient between counterpropagating lights, occurs only in systems lacking inversion symmetry. The introduction of temperature-gradient in an inversion-symmetric system will also yield nonreciprocal directional dichroism effect. This effect is then applied to quantum magnetism, where conventional experimental techniques have difficulty detecting magnetic mobile excitations such as magnons or spinons exclusively due to the interference of phonons and local magnetic impurities. A model calculation is presented to further demonstrate this phenomenon
Thesis (PhD) — Boston College, 2021
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Physics
Zonzo, Giuseppe. "Quantum Information Theory in Condensed Matter Physics". Doctoral thesis, Universita degli studi di Salerno, 2017. http://hdl.handle.net/10556/2625.
Texto completoInthe“standard”Gizburg-Landauapproach,aphasetransitionisintimately connected to a local order parameter, that spontaneously breaks some symmetries. In addition to the “traditional” symmetry-breaking ordered phases, a complex quantum system exhibits exotic phases, without classical counterpart, that can be described, for example, by introducing non-local order parameters that preserve symmetries. In this scenario, this thesis aims to shed light on open problems, such as the localdistinguishabilitybetweengroundstatesofasymmetry-breakingordered phase and the classification of one dimensional quantum orders, in terms of entanglement measures, in systems for which the Gizburg-Landau approach fails. In particular, I briefly introduce the basic tools that allow to understand the nature of entangled states and to quantify non-classical correlations. Therefore, I analyze the conjecture for which the maximally symmetry-breaking ground states (MSBGSs) are the most classical ones, and thus the only ones selected in real-world situations, among all the ground states of a symmetry-breaking ordered phase. I make the conjecture quantitatively precise, by proving that the MSBGSs are the only ones that: i) minimize pairwise quantum correlations, as measured by the quantum discord; ii) are always local convertible, by only applying LOCC transformations; iii) minimize the residual tangle, satisfying at its minimum the monogamy of entanglement. Moreover,Ianalyzehowevolvesthedistinguishability,afterasuddenchange of the Hamiltonian parameters. I introduce a quantitative measure of distinguishability, in terms of the trace distance between two reduced density matrices. Therefore, in the framework of two integrable models that falls in two different classes of symmetries, i.e. XY models in a transverse magnetic field and the N-cluster Ising models, I prove that the maximum of the distinguishability shows a time-exponential decay. Hence, in the limit of diverging time, all the informations about the particular initial ground state disappear, even if a system is integrable. Far away from the Gizburg-Landau scenario, I analyze a family of fullyanalyticalsolvableonedimensionalspin-1/2models,namedtheN-clustermodels in a transverse magnetic field. Regardless of the cluster size N + 2, these modelsexhibitaquantumphasetransition,thatseparatesaparamagneticphase from a cluster one. The cluster phase coresponds to a nematic ordered phase or a symmetry-protected topological ordered one, for even or odd N respectively. Using the Jordan-Wigner transformations, it is possible to diagonalize these models and derive all their spin correlation functions, with which reconstruct their entanglement properties. In particular, I prove that these models have only a non-vanishing bipartite entanglement, as measured by the concurrence, between spins at the endpoints of the cluster, for a magnetic field strong enough. Moreover, I introduce the minimal set of nonlinear ground-states functionals to detect all 1-D quantum orders for systems of spin-1/2 and fermions. I show that the von Neumann entanglement entropy distinguishes a critical systemfromanoncriticalone,becauseofthelogarithmicdivergenceataquantum critical point. The Schmidt gap detect the disorder of a system , because it saturates to a constant value in a paramagnetic phase and goes to zero otherwise. The mutual information, between two subsystems macroscopically separated, identifiesthesymmetry-breakingorderedphases,becauseofitsdependenceon the order parameters. The topological order phases, instead, via their deeply non-locality, can be characterized by analyzing all three functionals. [edited by author]
In aggiunta alle tradizionali fasi ordinate con rottura spontanea di simmetria, ben descritte con un approccio alla Gizburg-Landau, dove una transizione di fase `e intimamente connessa alla rottura spontanea di qualche simmetria e ad un parametro d’ordine locale, un sistema quantistico presenta anche fasi esotiche,senzaanalogoclassico,chesonoperesempiocaratterizzatedaparametri d’ordine non locali, senza una necessaria rottura di simmetria. Partendo da questi presupposti, questa tesi si pone come obiettivo quello di fare luce su alcuni problemi ancora aperti, come la distinguibilit`a tra stati fondamentaliinsistemiquantisticiconrotturaspontaneadisimmetriaelaclassificazionedituttelefasipresentiinsistemiunidimensionalidispin-1/2efermioni, per i quali l’approccio alla Gizburg-Landau non fornisce una descrizione adeguata. Inparticolare,sid`aunaspiegazioneall’ipotesisecondolaqualeglistatifondamentali che rompono massimamente la simmetria sono quelli pi`u classici, e quindi selezionati dalla decoerenza dell’ambiente, tra tutti gli stati fondamentali,edenergeticamenteequivalenti,diunafaseordinataconrotturaspontanea di simmetria. Si dimostra, infatti, che gli stati che rompono massimamente la simmetria sono gli unici stati che soddisfano tre criteri di classicalit`a: i) minimizzano l’entanglement bipartito, come quantificato dalla discord; ii) sono gli uniciversocuituttiglialtristatifondamentalisonolocalmenteconvertibili,mediante LOCC; iii) minimizzano il tangle residuo, soddisfacendo al minimo la monogamia dell’entanglement. Viene analizzato, inoltre, come evolve la distinguibilit`a tra stati fondamentali, dopo un quench dei parametri Hamiltoniani. Dopo aver introdotto una misura quantitativa della distinguibilit`a, in termini della distanza tra due matrici densit`a ridotte, si dimostra, per due sistemi integrabili con diverse classi di simmetria, nel dettaglio il modello XY in campo magnetico e i modelli NclusterIsing,cheladistinguibilit`adecadeesponenzialmenteneltempoequindi, nel limite di tempi lunghi, tutte le informazioni sullo stato fondamentale di partenza si perdono, anche per sistemi integrabili, nei quali la termalizzazione non si verifica. LontanodalloscenarioGizburg-Landau,sianalizzaunafamigliadimodelli di spin-1/2 esattamente risolvibili, nel dettaglio i modelli N-cluster in campo magnetico, che mostrano una transizione tra una fase disordinata e una di tipo cluster, che pu`o essere nematica o topologica, rispettivamente per N pari o dispari. Usando le trasformazioni di Jordan-Wigner `e possibile diagonalizzare questi modelli, ricavare lo stato fondamentale, le funzioni di correlazione fermioniche e tutte le loro propriet`a di entanglement di. Si dimostra che questi modellinonhannoentanglementmultipartito,masoloentanglementbipartito, come misurato dalla concurrence, tra due spin alle estremit`a del cluster, per un campo magnetico sufficientemente intenso. Inoltre, sidimostrachel’entropiadivonNeumann,loSchmidtgapelamutualinformationrappresentanoilsetminimodifunzionalinonlinearidellamatrice densit`a ridotta, mediante le quali caratterizzare tutte le fasi presenti in sistemi unidimensionali di spin -1/2 e fermioni. In particolare, l’entropia di von Neumann caratterizza la criticalit`a del sistema, per la sua divergenza logaritmica al punto critico; lo Schmidt gap caratterizza il disordine di un sistema, perch´e satura ad un valore costante nelle fasi disordinate e va rapidamente a zero altrove; la mutual information cattura le fasi ordinate con rottura spontanea di simmetria, per le quali cio` e `e possibile definire un parametro d’ordine diverso da zero su un supporto finito. Le fasi topologiche, per via della loro natura fortemente non locale, necessitano di tutte e tre i funzionali per essere individuate. [a cura dell'autore]
XV n.s.
Barranco, López Alejandro. "Applications of Supersymmetry: Exact Results, Gauge/Gravity Duality and Condensed Matter". Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/284195.
Texto completoEl estudio de supersimetría nos ha permitido un mejor entendimiento de las teorías de campos, especialmente en el régimen de acoplamiento fuerte. En esta tesis hemos tratado de mostrar esto a través de varios ejemplos. A saber: - Primero hemos mostrado cómo calcular de manera exacta con técnicas de localización la función de partición de la teoría de Chern-Simons supersimétrica N=2 con grupo gauge U(N) y 2Nf sabores en una tres esfera. Una vez que tenemos la función de partición exacta en términos de una integral de matrices, podemos resolverla por medio de la aproximación de punto silla. Esta aproximación se vuelve exacta cuando tomamos el límite de N grande. En el límite de descompactificación calculamos la energía libre y el valor de expectación de un lazo de Wilson correspondiente a un círculo máximo de la tres-esfera, mostrando transiciones de fase de tercer orden. - Otra aplicación ha consistido en el uso de la dualidad gravedad/gauge. Hemos revisado como construir una solución de supergravedad dual a la teoría N=1 super Yang-Mills con Nf sabores masivos y un superpotencial cuártico. El principal resultado desde el punto de vista de la teoría de campos que corresponde a dicha solución, consiste en que, en el caso Nf=2N, la función beta exhibe un punto fijo UV no trivial que da lugar a indicios acerca de un punto fijo IR adicional tal y como propone Seiberg en su propuesta de la ventana conforme. - También en el contexto de la dualidad gravedad/gauge hemos estudiado cómo generar nuevas soluciones de supergravedad por medio de la aplicación de T-dualidad a la solución de supergravedad de Klebanov y Witten con sabores. La supersimetría de estas soluciones pueden ser descritas en términos de una SU(3) estructura antes de T-dualizar, o una SU(2)-estructura, después de T-dualizar. - Finalmente, hemos presentado un modelo supersimétrico que exhibe una transición de fase superconductora basado en un potencial de Kähler cuártico para un multiplete quiral y sin superpotencial. Encontramos dos diferencias con superconductores usuales: nuestro modelo exhibe una transición de fase de primer orden, en lugar de ser de segundo orden, y la dependencia con la energía de corte es más suave.
Liyanage, Geethika Kaushalya. "Infrared Emitting PbS Nanocrystals through Matrix Encapsulation". Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1403953924.
Texto completoRunge, Katharina. "Visualisation de fluxoides dans des réseaux 2D artificiels supraconducteurs". Phd thesis, Grenoble 1, 1993. http://tel.archives-ouvertes.fr/tel-00356016.
Texto completoDuki, Solomon Fekade. "Topics in Hard and Soft Condensed Matter Physics". Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1232737384.
Texto completoMosconi, Paola. "Ghost Models in Two-Dimensional Condensed Matter Physics". Doctoral thesis, SISSA, 2003. http://hdl.handle.net/20.500.11767/4205.
Texto completoWoo, Jung Min. "Two mathematical problems in disordered systems". Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/289124.
Texto completoPosavec, Tony. "An Investigation into the Fluorescence of Polymers". University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1499353221343727.
Texto completoVarea, Emilien. "Experimental analysis of laminar spherically expanding flames". Phd thesis, INSA de Rouen, 2013. http://tel.archives-ouvertes.fr/tel-00800616.
Texto completoJung, Young Woo. "Optical studies and biological applications of spins in semiconductors". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306523724.
Texto completoBabadi, Mehrtash. "Non-equilibrium dynamics of artificial quantum matter". Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11114.
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De, Silva Theja Nilantha. "Spin-Orbital Physics in Transition Metal Oxides". University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1092948911.
Texto completoPike, Nicholas A. "Energy Dispersion, Magnetism, and Transport in Three Condensed Matter Systems". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1417604062.
Texto completoSmith, Gregory J. "Application of Attosecond Techniques to Condensed Matter Systems". The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1608496995249541.
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