Browsing by Subject "Quàntums, Teoria dels"
Now showing items 1-20 of 81
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A Combinatorial Approach to Nonlocality and Contextuality
(Springer, 2015-03-01)
Article
Open AccessSo far, most of the literature on (quantum) contextuality and the Kochen– Specker theorem seems either to concern particular examples of contextuality, or be considered as quantum logic. Here, we develop a general formalism ... -
A general framework for information-work interconvertibility in the quantum regime
(Universitat Politècnica de Catalunya, 2016-09)
Master thesis
Open AccessIn this theoretical work we study three theorems that establish limitations to three basic processes in thermodynamics: an adiabatic process, an erasure process and a work extraction process. We propose a theoretical setting ... -
Almost quantum correlations
(Nature Publishing group, 2015-02-20)
Article
Open AccessQuantum theory is not only successfully tested in laboratories every day but also constitutes a robust theoretical framework: small variations usually lead to implausible consequences, such as faster-than-light communication. ... -
An experimental setup for gray molasses sub-Doppler cooling of potassium gases
(Universitat Politècnica de Catalunya, 2014-09-09)
Master thesis
Open Access[ÀNGLÈS] An experimental setup for cooling a gas of potassium atoms below the Doppler limit is presented. This method is known as gray molasses cooling. It will be implemented using light blue light blue detuned with respect ... -
Applications of machine learning to studies of quantum phase transitions
(Universitat Politècnica de Catalunya, 2019-09-06)
Master thesis
Open AccessIn the past years Machine Learning has shown to be a useful tool in quantum many-body physics to detect phase transitions. Being able to identify phases via machine learning introduces the question of how did the algorithm ... -
Bloch oscillations in optical and Zeeman lattices in the presence of spin-orbit coupling
(2016-11-18)
Article
Open AccessWe address Bloch oscillations of a spin-orbit coupled atom in periodic potentials of two types: optical and Zeeman lattices. We show that in optical lattices the spin-orbit coupling allows controlling the direction of ... -
Bose polarons at finite temperature and strong coupling
(2018-02-01)
Article
Open AccessA mobile impurity coupled to a weakly interacting Bose gas, a Bose polaron, displays several interesting effects. While a single attractive quasiparticle is known to exist at zero temperature, we show here that the spectrum ... -
Bound states in the continuum in anisotropic structures
(Institute of Electrical and Electronics Engineers (IEEE), 2017)
Conference report
Restricted access - publisher's policyWe report theoretical and experimental observation of radiationless bound states in the continuum (BIC) in waveguiding anisotropic structures. BICs may have all possible polarizations and be the only possible boundstates ... -
Bound states in the continuum in spin-orbit-coupled atomic systems
(2017-09-14)
Article
Restricted access - publisher's policyWe show that the interplay between spin-orbit coupling and Zeeman splitting in atomic systems can lead to the existence of bound states in the continuum (BICs) supported by trapping potentials. Such states have energies ... -
Can quantum effects due to a massless conformally coupled field avoid gravitational singularities?
(2012-04)
Article
Restricted access - publisher's policyUsing quantum corrections from massless fields conformally coupled to gravity, we study the possibility of avoiding singularities that appear in the flat Friedmann–Robertson–Walker model. We assume that the universe ... -
Coherent control of a superconducting quantum bit
(Universitat Politècnica de Catalunya, 2019-09-06)
Master thesis
Open AccessTransmon qubits are at the forefront of solid state platforms for quantum computing. In this thesis, results obtained from the experimental study of a transmon qubit in a 3D cavity are presented. A complete view of the ... -
Complexity Reduction in Large Quantum Systems: Fragment Identification and Population Analysis via a Local Optimized Minimal Basis
(American Chemical Society, 2017-07-21)
Article
Open AccessWe present, within Kohn–Sham density functional theory calculations, a quantitative method to identify and assess the partitioning of a large quantum-mechanical system into fragments. We then show how within this framework ... -
Computación cuántica : nuevas perspectivas en el tratamiento de la información
(Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 2000)
Article
Open Access -
Conformal data from finite entanglement scaling
(APS Physics, 2015-01-20)
Article
Open AccessIn this paper, we apply the formalism of translation invariant (continuous) matrix product states in the thermodynamic limit to (1 + 1)-dimensional critical models. Finite bond dimension bounds the entanglement entropy ... -
Detection of nonlocality with two-body correlation functions
(Universitat Politècnica de Catalunya, 2015-09-10)
Master thesis
Open AccessNonlocality detection in multipartite quantum systems is of great interest. The most popular tool to detect nonlocality in quantum systems are Bell inequalities. Most of the provided constructions of multipartite Bell ... -
Dynamic structure factor of liquid He 4 across the normal-superfluid transition
(2016-03-08)
Article
Open AccessWe have carried out a microscopic study of the dynamic structure factor of liquid He4 across the normal-superfluid transition temperature using the path integral Monte Carlo method. The ill-posed problem of the inverse ... -
El Efecto túnel resonante de la magnetización a escala macroscópica abre las puertas de la computación cuántica
(Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 1997)
Article
Open Access -
Enhanced discretization of surface integral equations for resonant scattering analysis of sharp-edged plasmonic nanoparticles
(American Physical Society (APS), 2019-04-10)
Article
Open AccessThe surface integral equation (SIE) method, discretized with the method of moments, is a well-established methodology for the scattering analysis of subwavelength plasmonic nanoparticles. SIEs are usually discretized with ... -
Entanglement and non-locality of pure quantum states.
(Universitat Politècnica de Catalunya, 2010-07-19)
Master thesis
Open AccessWe study the process of majorisation and interconversion of bipartite states, and apply the formalism for analysing the local and non-local content of pure bipartite entangled states. We proved that the states which are ... -
Explorations of thermodynamics and information in quantum field theory
(Universitat Politècnica de Catalunya, 2020-05-20)
Bachelor thesis
Open Access
Covenantee: Institute for Quantum Computing (University of Waterloo) / University of WaterlooPodria dir-se que la termodinàmica ha sigut una de les rames més poderoses de la física, i la més universal per la seva varietat d'aplicacions. Des de motors de vapor fins a forats negres, les lleis de la termodinàmica ...