Now showing items 1-20 of 34

    • A general framework for information-work interconvertibility in the quantum regime 

      Rodríguez Ramos, Constantino (Universitat Politècnica de Catalunya, 2016-09)
      Master thesis
      Open Access
      In 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 ...
    • Anomalous diffusion : from life to machines 

      Muñoz Gil, Gorka (Universitat Politècnica de Catalunya, 2020-11-09)
      Doctoral thesis
      Open Access
      Diffusion refers to numerous phenomena, by which particles and bodies of all kinds move throughout any kind of material, has emerged as one of the most prominent subjects in the study of complex systems. Motivated by the ...
    • Applications of a quantum random number generator to simulations in condense matter physics 

      Guigó Corominas, Guillem (Universitat Politècnica de Catalunya, 2018-10-15)
      Master thesis
      Open Access
      Covenantee:   Institut de Ciències Fotòniques (ICFO)
      We study the importance of the quality of random numbers in Monte Carlo simulations of 2D Ising systems. Simulations are carried out at critical temperature to find the dynamic scaling law of the linear relaxation time. ...
    • Applications of machine learning to studies of quantum phase transitions 

      Malo Roset, Laura (Universitat Politècnica de Catalunya, 2019-09-06)
      Master thesis
      Open Access
      In 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 ...
    • A cold-atom approach to topological quantum matter across the energy scale 

      González Cuadra, Daniel (Universitat Politècnica de Catalunya, 2020-12-11)
      Doctoral thesis
      Open Access
      The outstanding progress achieved in the last decades to isolate and manipulate individual quantum systems has revolutionized the way in which quantum many-body phenomena, appearing across Nature's different energy scales, ...
    • Complex systems for quantum technologies 

      Braungardt, Sibylle (Universitat Politècnica de Catalunya, 2011-07-12)
      Doctoral thesis
      Open Access
    • Condensed matter meets deep learning: from spins to neurons 

      Piñol Jimenez, Eloy (Universitat Politècnica de Catalunya, 2020-09-09)
      Master thesis
      Open Access
      In the recent years, Machine Learning (ML) techniques have irrupted in many sectors, from industry to scientific research, and is expected that their presence will grow even more in upcoming years. While their use grows, ...
    • Controlling interactions in quantum materials : from a microscopic description to quantum simulation 

      Julià Farré, Sergi (Universitat Politècnica de Catalunya, 2022-06-28)
      Doctoral thesis
      Open Access
      The last decades have witnessed impressive technical advances in all the fields of quantum science, including solid-state systems or atomic, molecular, and optical physics, allowing one to control materials at the microscopic ...
    • Detection of quantum phase transitions via machine learning algorithms 

      Pérez Díaz, Joel (Universitat Politècnica de Catalunya, 2019-08-31)
      Master thesis
      Open Access
      A Neural Network is trained to classify Mott Insulator and Superfluid phases in an optical lattice using data generated with Diffusion Monte Carlo algorithms (DMC). The trained model is used to predict the phase transition ...
    • Dynamics of quantum mixtures 

      Guenther, Nils Eric (Universitat Politècnica de Catalunya, 2021-09-08)
      Doctoral thesis
      Open Access
      At sufficiently low temperatures, fluids of bosonic particles may undergo a phase transition, below which a Bose-Einstein condensate (BEC) forms. The BEC is one of the most fundamental concepts in many-body quantum physics ...
    • Dynamics of spinor fermions 

      Ebling, Ulrich (Universitat Politècnica de Catalunya, 2014-11-03)
      Doctoral thesis
      Open Access
      Ultracold atomic gases have established themselves as quantum systems, which are clean and offer a high degree of control over crucial parameters. They are well isolated from their environment and thus offer the possibility ...
    • Entanglement and Bell correlations in strongly correlated many-body quantum systems 

      Piga, Angelo (Universitat Politècnica de Catalunya, 2020-03-30)
      Doctoral thesis
      Open Access
      During the past two decades, thanks to the mutual fertilization of the research in quantum information and condensed matter, new approaches based on purely quantum features without any classical analog turned out to be ...
    • Exact diagonalization studies of quantum simulators 

      Raventós Ribera, David (Universitat Politècnica de Catalunya, 2019-04-15)
      Doctoral thesis
      Open Access
      Understand and tame complex quantum mechanical systems to build quantum technologies is one of the most important scientific endeavour nowadays. In this effort, Atomic, molecular and Optical systems have clearly played a ...
    • Experimental evidence for the quantum condensation of ultracold dipolar excitons 

      Alloing, Mathieu (Universitat Politècnica de Catalunya, 2014-05-28)
      Doctoral thesis
      Open Access
      In this thesis, we report experimental evidence of a "gray" condensate of excitons, as predicted theoretically by M. Combescot et al. Most importantly, the condensate is characterized by the macroscopic population of dark ...
    • Exploring quantum many-body systems from an entanglement and nonlocality perspective 

      Aloy López, Albert (Universitat Politècnica de Catalunya, 2020-07-16)
      Doctoral thesis
      Open Access
      Entanglement and non-local correlations give rise to unprecedented phenomena with no classical analogue. As a result, they have settled themselves as fundamental properties in the study of quantum many-body systems, as ...
    • Extracting relevant physical parameters with ß-variational autoencoders 

      Fernández Fernández, Gabriel (Universitat Politècnica de Catalunya, 2020-09-09)
      Master thesis
      Open Access
      During the last years, machine learning techniques have been applied todiscover properties of physical systems. However, these algorithms are black boxesand there is a need for tools to interpret them. ...
    • Investigations of topological phases for quasi-1D systems 

      Tirrito, Emanuele (Universitat Politècnica de Catalunya, 2020-07-13)
      Doctoral thesis
      Open Access
      For a long time, quantum states of matter have been successfully characterized by the Ginzburg-Landau formalism that was able to classify all different types of phase transitions. This view changed with the discovery of ...
    • Nonergordic Subdiffusion of a Random-walker from Interactions with Heterogeneous Partners 

      Muñoz Gil, Gorka (Universitat Politècnica de Catalunya, 2016-09-08)
      Master thesis
      Open Access
      Understanding the motion of particles in biological systems is key in many applications such as drug precision delivery, living-cells characterization, etc. The dynamics of a particle in many of these systems is often ...
    • Optical emulator of two atoms in a double well 

      Fabra Ruiz, Arnau (Universitat Politècnica de Catalunya, 2019-09-09)
      Master thesis
      Open Access
      We show that optical fibers with an inhomogeneous refractive index profile and thin metallic slabs can be used to simulate a one dimensional system of two interacting particles in a double well. We first study the single ...
    • Probing and realising long range topological superconductivity 

      Mestre Torrents, Carles (Universitat Politècnica de Catalunya, 2021-09-08)
      Master thesis
      Open Access
      Covenantee:   Universitat de Barcelona / Universitat Autònoma de Barcelona
      In recent years, there has been a lot of work, that has focused on studying Ising spin chains with tunable long-range interactions. Such chains can now, for instance, be experimentally realized using ultracold atoms or in ...