Now showing items 1-20 of 30

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

    Salazar Serrano, Luis José (Universitat Politècnica de Catalunya, 2012-09-06)
    Master thesis
    Open Access
    [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)
    Master thesis
    Open Access
    [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)
    Master thesis
    [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 ...
  • Detection of graphene motion through light-matter interactions 

    Schädler, Kevin Gerd (Universitat Politècnica de Catalunya, 2012-09-06)
    Master thesis
    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 ...
  • Digital coherent receiver for orbital angular momentum demultiplexing 

    Belmonte Molina, Aniceto; Pérez Torres, Juan (2013-01-15)
    Article
    Open Access
    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 CatalunyaUniversitat Autònoma de Barcelona, 2012-09-04)
    Master thesis
    Open Access
    [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 CatalunyaUniversitat Autònoma de Barcelona, 2012-09-04)
    Master thesis
    Open Access
    [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)
    Master thesis (pre-Bologna period)
    Open Access
    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
    Restricted access - publisher's policy
    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)
    Master thesis
    Open Access
    [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 ...
  • 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
    Restricted access - publisher's policy
    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 ...
  • Generation of polarization entangled photon pairs in Bragg reflection waveguides 

    Vallés Marí, Adam (Universitat Politècnica de Catalunya, 2012-09-06)
    Master thesis
    Open Access
    [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 ...
  • Harnessing magneto-electric interference to direct light emission with a split-ring resonator 

    Hancu, Ion Michael (Universitat Politècnica de Catalunya, 2012-09-03)
    Master thesis
    Open Access
    [ANGLÈS] Here we show that a split-ring resonator, a structure widely known for its magnetic response at optical frequencies, can be used as a robust, unidirectional and broadband nanoantenna. By customizing its dimensions ...
  • Laser frequency stabilization to excited Rydberg transitions using electromagnetically induced transparency 

    Grimau Puigibert, Marcel·lí (Universitat Politècnica de Catalunya, 2012-09-10)
    Master thesis
    Open Access
    [ANGLÈS] Rydberg atoms with principal quantum number n>>1 have extraordinary atomic properties including tunable long range dipole-dipole interactions that lead to the so called Rydberg blockade. Atoms excited to these ...
  • Preparation of entangled Dicke states using atomic ensembles 

    Franquet González, Albert (Universitat Politècnica de Catalunya, 2013-09-09)
    Master thesis
    [ANGLÈS] Phenomena associated with collective interactions in atom-nanofiber interfaces have been of great interest. Here, we show how multipartite entanglement in atomic ensembles can emerge from collective emission in ...
  • Propagation of collective modes in non-overlapping dipolar Bose-Einstein condensates 

    Gallemí Camacho, Alberto (Universitat Politècnica de Catalunya, 2013-07-19)
    Master thesis
    Open Access
    [ANGLÈS] We have studied the propagation of different collective modes of excitation (dipolar, monopolar and quadrupolar) in double and triple-well configurations in dipolar Bose-Einstein Condensates, due to the long-range ...
  • Puentes, Hermosa, and Torres reply 

    Puentes, Graciana; Hermosa, Nathaniel; Pérez Torres, Juan (2013-07-10)
    Article
    Open Access
    A Reply to the Comment by A. K. Pan and P. K. Panigrahi.
  • Quantum atom-light interfaces in the Gaussian description for spin-1 systems 

    Colangelo, Giorgio; Sewell, Robert J.; Behbood, Naeimeh; Ciurana, Ferran Martin; Triginer Cahelles, Joaquim; Mitchell, Morgan W. (2013-10)
    Article
    Open Access
    We extend the covariance matrix description of atom–light quantum interfaces, originally developed for real and effective spin-1/2 atoms, to include ‘spin alignment’ degrees of freedom. This allows accurate modelling ...
  • Quantum Control of Cold Atoms using microwaves 

    Martin Ciurana, Ferran (Universitat Politècnica de Catalunya, 2011-09-08)
    Master thesis
    Open Access
    English: We study quantum control of the ground hyperfine manifold of alkali-metal atoms based on applied microwave fields. We performed microwave spectroscopy both in the frequency and the time domain resulting in the ...
  • Quantum effects and gap morphology in the optical response of plasmonic gap-nanoantennas 

    Aguirregabiria Achutegui, Garikoitz (Universitat Politècnica de Catalunya, 2013-09-09)
    Master thesis
    [ANGLÈS] Optical gap-nanoantennas are basic building blocks to control light at the nanoscale. We study how the morphology of the gap affects the response of the nanoantennas. A classical study shows that in spherical gaps ...