Ara es mostren els items 1-20 de 50

  • A super frequency-shifter: enhancing the capabilities of acousto-optic modulators 

    Salazar Serrano, Luis José (Universitat Politècnica de Catalunya, 2012-09-06)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] We put forward a new scheme to enhance the capabilities of currently available acousto-optic frequency shifters (AOFS) by making use of the idea of weak value amplification. The key result of our approach is that ...
  • Characterization of a quantum frequency converter for quantum repeater applications 

    Fernandez Gonzalvo, Xavier (Universitat Politècnica de Catalunya, 2012-09-03)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] Quantum frequency conversion of quantum memory compatible photons to telecom wavelength is a requirement for the implementation of scalable quantum repeaters, a key ingredient for long distance quantum communications ...
  • Classical simulation of restricted quantum computations 

    Nebhwani, Mrityunjaya (Universitat Politècnica de Catalunya, 2013-09-09)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] We study restricted models of measurement-based quantum computation; and we investigate whether their output probability distributions can be sampled from efficiently on a classical computer. We find that even for ...
  • Demonstration of a highly-sensitive tunable beam displacer with no use of beam deflection based on the concept of weak value amplification 

    Salazar Serrano, Luis Jose; Guzman, David A; Valencia, Alejandra; Pérez Torres, Juan (2015-04-10)
    Article
    Accés restringit per política de l'editorial
    We report the implementation of a highly sensitive tunable beam displacer based on the concept of weak value amplification, that allows to displace the centroid of a Gaussian beam a distance much smaller than its beam width ...
  • Design and construction of optical superlattices for a quantum gas experiment 

    Sastre Pellicer, Jordi (Universitat Politècnica de Catalunya, 2015-10)
    Treball Final de Grau
    Accés obert
    In recent years ultracold atomic gases have emerged as a new and promising platform for exploring the physics of quantum many-body systems, allowing researchers to revisit fundamental problems of condensed-matter physics ...
  • Detection loophole attacks on semi-device-independent quantum and classical protocols 

    Dall’Arno, Michele; Passaro, Elsa; Gallego, Rodrigo; Pawlowski, Marcin; Acín, Antonio (Rinton Press, 2015-01-01)
    Accés obert
    Semi-device-independent quantum protocols realize information tasks – e.g. secure key distribution, random access coding, and randomness generation – in a scenario where no assumption on the internal working of the devices ...
  • Detection of entanglement in asymmetric quantum networks and multipartite quantum steering 

    Cavalcanti, D.; Skrzypczyk, P.; Aguilar, G. H.; Souto Ribeiro, P. H.; Walborn, S. P. (Nature Publishing Group, 2015-08-03)
    Article
    Accés obert
    The future of quantum communication relies on quantum networks composed by observers sharing multipartite quantum states. The certification of multipartite entanglement will be crucial to the usefulness of these networks. ...
  • Detection of graphene motion through light-matter interactions 

    Schädler, Kevin Gerd (Universitat Politècnica de Catalunya, 2012-09-06)
    Projecte Final de Màster Oficial
    60 months embargo
    [ANGLÈS] In this thesis, we study both experimentally and theoretically the optical detection of the motion of graphene membranes based on fluorescence quenching of the emitters close to graphene. Fluorescence quenching ...
  • Development of a fluorescence imaging system for a quantum gas experiment 

    Sanz Sánchez, Julio (Universitat Politècnica de Catalunya, 2015-09-10)
    Projecte Final de Màster Oficial
    Accés obert
    Realitzat a/amb: Universitat Autònoma de Barcelona / Realitzat a/amb: Institut de Ciències Fotòniques (ICFO) / Realitzat a/amb: Universitat de Barcelona
    In this report we present a technique for imaging the momentum distribution of an ultracold atomic gas in 3D and with single atom resolution. We describe the first experimental steps taken to implement it in a quantum gas ...
  • Digital coherent receiver for orbital angular momentum demultiplexing 

    Belmonte Molina, Aniceto; Pérez Torres, Juan (2013-01-15)
    Article
    Accés obert
    We put forward a type of receiver for coherent detection of the photon orbital angular momentum (OAM). A coherent array receiver, consisting of multiple subapertures, with each subaperture coupled to a single-mode fiber, ...
  • Dynamics of a Bose Einstein condensate in a ring potential 

    Pino Quintana, Hernán (Universitat Politècnica de Catalunya / Universitat Autònoma de Barcelona, 2012-09-04)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] We have addressed the dynamics of a repulsive interacting 87 Rb Bose Einstein condensate (BEC) in a ring potential trap. Our study has been focused in the analysis of the interference pattern that arises by the ...
  • Dynamics of matter wave solitons 

    Polo Gómez, Juan (Universitat Politècnica de Catalunya / Universitat Autònoma de Barcelona, 2012-09-04)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] We study the implementation of a matter wave bright soliton interferometer formed by a Gaussian potential barrier placed at the center of a harmonic trap potential. After numerically evaluating the transmission ...
  • Efficient generation of new optical wavelengths by means of second harmonic generation in AlGaAs Bragg reflection waveguides 

    Valles Mari, Adam (Universitat Politècnica de Catalunya, 2011-09-19)
    Projecte/Treball Final de Carrera
    Accés obert
    English: In this project has been designed and implemented a setup to produce the nonlinear process of the second harmonic generation (SHG) in Bragg reflection waveguides (BRW). Starting with the adjustment of a tunable ...
  • Efficient heralding of polarization-entangled photons from type-0 and type-II spontaneous parametric downconversion in periodically poled KTiOPO 4 

    Steinlechner, Fabian; Gilaberte, Marta; Jofre, Marc; Scheidl, Thomas; Pérez Torres, Juan; Pruneri, Valerio; Ursin, Rupert (2014-09-01)
    Article
    Accés restringit per política de l'editorial
    Ultrabright sources of entangled photon pairs with high heralding efficiency are an important step in the pursuit of high-bit-rate entanglement-base quantum key distribution, as well as an enabling tool for loss-sensitive ...
  • Entangled Photon Source for Single Molecule Microscopy 

    Abbasi Zargaleh, Soroush (Universitat Politècnica de Catalunya, 2013-02-11)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] This paper presents experimental implementation of highly correlated photons for single molecules microscopy application. We designed and built a Type-II Spontaneous Parametric Down Conversion (SPDC) photon pair ...
  • Entanglement and Nonlocality are Inequivalent for Any Number of Parties 

    Augusiak, R.; Demianowicz, M.; Tura, J.; Acín, Antonio (APS, 2015-07-15)
    Article
    Accés obert
    Understanding the relation between nonlocality and entanglement is one of the fundamental problems in quantum physics. In the bipartite case, it is known that these two phenomena are inequivalent, as there exist entangled ...
  • Flux enhancement of photons entangled in orbital angular momentum 

    Palacios, Silvana; León Montiel, R.D.J.; Hendrych, Martin; Valencia, Alejandra; Pérez Torres, Juan (2011-07-18)
    Article
    Accés restringit per política de l'editorial
    Entangled photons are generally collected by detection systems that select their certain spatial modes, for example using single-mode optical fibers. We derive simple and easy-to-use expressions that allow us to maximize ...
  • Fragmented condensation in Bose–Hubbard trimers with tunable tunnelling 

    Gallemí, A.; Guilleumas, M.; Martorell, J.; Mayol, R.; Polls, A.; Juliá-Díaz, Bruno (IOP, 2015-07-15)
    Article
    Accés obert
    We consider a Bose–Hubbard (BH) trimer, i.e. an ultracold Bose gas populating three quantum states. The latter can be either different sites of a triple-well potential or three internal states of the atoms. The bosons can ...
  • Generation of polarization entangled photon pairs in Bragg reflection waveguides 

    Vallés Marí, Adam (Universitat Politècnica de Catalunya, 2012-09-06)
    Projecte Final de Màster Oficial
    Accés obert
    [ANGLÈS] We report the observation of polarization entangled photon pairs generated by means of type-II spontaneous parametric down-conversion (SPDC) within an AlGaAs Bragg reflection waveguide (BRW). Even though SPDC in ...
  • Globally-linked vortex clusters 

    Crasovan, L C; Vekslerchik, V; Mihalache, Dumitru; Pérez Torres, Juan; Perez-Garcia, V M; Torner Sabata, Lluís (Kluwer, 2004-09-30)
    Capítol de llibre
    Accés restringit per política de l'editorial
    We show the existence of a rich variety of fully stationary vortex structures made of an increasing number of vortices nested in paraxial wave fields confined by symmetric and asymmetric harmonic trapping potentials in ...