Now showing items 1-20 of 38

  • A Combinatorial Approach to Nonlocality and Contextuality 

    Acin, Antonio; Fritz, Tobias; Leverrier, Anthony (Springer, 2015-03-01)
    Article
    Open Access
    So 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 ...
  • Almost quantum correlations 

    Navascués, Miguel; Guryanova, Yelena; Hoban, Matty J.; Acín, Antonio (Nature Publishing group, 2015-02-20)
    Article
    Open Access
    Quantum 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 

    Bosch Aguilera, Manel (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 ...
  • Can quantum effects due to a massless conformally coupled field avoid gravitational singularities? 

    Haro Cases, Jaume (2012-04)
    Article
    Restricted access - publisher's policy
    Using 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 ...
  • Computación cuántica : nuevas perspectivas en el tratamiento de la información 

    Salas Peralta, Pedro J.; Sanz Sáenz, Ángel L. (Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 2000)
    Article
    Open Access
  • Conformal data from finite entanglement scaling 

    Stojevic, Vid; Haegeman, Jutho; McCulloch, I. P.; Tagliacozzo, Luca; Verstraete, Frank (APS Physics, 2015-01-20)
    Article
    Open Access
    In 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 

    Aloy López, Albert (Universitat Politècnica de Catalunya, 2015-09-10)
    Master thesis
    Open Access
    Nonlocality 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 ...
  • El Efecto túnel resonante de la magnetización a escala macroscópica abre las puertas de la computación cuántica 

    del Barco, E.; Hernández, J. M.; Ziolo, R. F.; Tejada, J. (Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 1997)
    Article
    Open Access
  • Entanglement and non-locality of pure quantum states. 

    Sainz, Ana Belén (Universitat Politècnica de Catalunya, 2010-07-19)
    Master thesis
    Open Access
    We 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 ...
  • Física cuántica : interferencias, correlaciones y realidad 

    Scarani, Valerio (Iniciativa Digital Politècnica, 2015)
    Book
    Restricted access to the UPC academic community
    La física cuántica se ha erigido como uno de los pilares fundamentales sobre los cuales se asienta la física moderna. Es una puerta a un mundo fascinante, de características sorprendentes; un microcosmos regido por la ...
  • From poly(3,4-ethylenedioxythiophene) to poly(3,4-phenylenedioxythiophene) : impact of the ethylene bridge by the phenyl ring in the molecular propierties 

    Carrión Fajardo, Sergio (Universitat Politècnica de Catalunya, 2010-09)
    Master thesis
    Restricted access - author's decision
    The structural and electronic properties of poly(3,4-phenylenedioxythiophene) and poly(3,4- ethylenedioxythiophene) have been studied using quantum mechanical methods. Calculations have been performed considering a series ...
  • Highly efficient noise-assisted energy transport in classical oscillator systems 

    Leon Montiel, R de J.; Pérez Torres, Juan (2013-05)
    Article
    Open Access
    Photosynthesis is a biological process that involves the highly-efficient transport of energy captured from the sun to a reaction center, where conversion into useful biochemical energy takes place. Even though one can ...
  • Inequivalence of entanglement, steering, and Bell nonlocality for general measurements 

    Quintino, Marco Tulio; Vértesi, Tamas; Cavalcanti, Daniel; Augusiak, Remigiusz; Demianowicz, Maciej; Acín, Antonio; Brunner, Nicolas (APS, 2015-09-08)
    Article
    Open Access
    Einstein-Podolsky-Rosen steering is a form of inseparability in quantum theory commonly acknowledged to be intermediate between entanglement and Bell nonlocality. However, this statement has so far only been proven for a ...
  • Llenguatges de Programació Quàntica 

    Marcos Pitarch, Eric (Universitat Politècnica de Catalunya, 2009-06)
    Master thesis (pre-Bologna period)
    Open Access
    Aprofundir en els coneixements de computació quàntica, tant des del vessant de la física com des del vessant de la teoria de la computació, que em situïn en un punt de "pre-recerca". Tenir un mapa de les diferents ...
  • Local discrimination of rotationally invariant states 

    Ronco Bonvehi, Elio (Universitat Politècnica de CatalunyaUniversitat Autònoma de Barcelona, 2010)
    Master thesis
    Open Access
    We provide lower bounds for the minimum error discrimination probability of multipartite rotationally invariant states using separable measurements. The separability of the measurement operators has been investigated, ...
  • Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres 

    Hensen, B.; Bernien, H.; Dréau, A. E.; Reiserer, A.; Kalb, N.; Blok, M. S.; Ruitenberg, J.; Vermeulen, R. F. L.; Schouten, R. N.; Abellán, C.; Amaya, W.; Pruneri, P.; Mitchell, Morgan W.; Markham, M.; Twitchen, D. J.; Elkouss, D.; Wehner, S.; Taminiau, T. H.; Hanson, R. (Nature Publishing Group, 2015-10-21)
    Article
    Restricted access - publisher's policy
    More than 50 years ago1, John Bell proved that no theory of nature that obeys locality and realism2 can reproduce all the predictions of quantum theory: in any local-realist theory, the correlations between outcomes of ...
  • Macroscopic Quantum State Analyzed Particle by Particle 

    Beduini, Federica A.; Zielińska, Joanna A.; Lucivero, Vito G.; Icaza Astiz, Yannick A. de; Mitchell, Morgan W. (ACS Publications, 2015-03-27)
    Article
    Open Access
    Macroscopic quantum phenomena, e.g., superconductivity and squeezing, are believed to result from entanglement of macroscopic numbers of particles. We report the first direct study of this kind of entanglement: we use ...
  • Maximally Nonlocal Theories Cannot Be Maximally Random 

    Torre, Gonzalo de la; Hoban, Matty J.; Dhara, Chirag; Prettico, Giuseppe; Acín, Antonio (APS, 2015-04-22)
    Article
    Open Access
    Correlations that violate a Bell inequality are said to be nonlocal; i.e., they do not admit a local and deterministic explanation. Great effort has been devoted to study how the amount of nonlocality (as measured by a ...
  • Methods for solving 1D Stefan problems with application to contact melting 

    De Decker, Michelle (Universitat Politècnica de Catalunya, 2011-05)
    Master thesis
    Open Access
    Contact melting is the process during which a phase change material is placed in contact with a substrate that is at a temperature above the phase change temperature. This leads to melting of the phase change material and ...
  • Phase diagram of a quantum Coulomb wire 

    Ferré Porta, Guillem; Astrakharchik, Grigori; Boronat Medico, Jordi (2015-12-09)
    Article
    Open Access