Exploració per tema "Quantum optics"

Ara es mostren els items 50-69 de 93

    • Phase Diffusion effects in InP semiconductor lasers 

      Martínez Pàmias, Berta (Universitat Politècnica de Catalunya, 2022-09-06)
      Projecte Final de Màster Oficial
      Accés restringit per acord de confidencialitat

    • Practical implementation of a continuous-variable quantum key distribution system 

      Hernández Aguirre, Leiza (Universitat Politècnica de Catalunya, 2018-06-26)
      Treball Final de Grau
      Accés restringit per decisió de l'autor
      Realitzat a/amb:   Institut de Ciències Fotòniques (ICFO)
      Quantum key distribution with continuous variables (CV-QKD) enables two parties to share a secret key by using coherent states of light and homodyne detection. This can be carried out by employing low-cost and mature ...

    • Preparation of entangled Dicke states using atomic ensembles 

      Franquet González, Albert (Universitat Politècnica de Catalunya, 2013-09-09)
      Projecte Final de Màster Oficial
      Accés obert
      [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 ...

    • Probing the strongly driven spin-boson model in a superconducting quantum circuit 

      Magazzù, Luca; Forn Diaz, Pol; Belyansky, Ron; Orgiazzi, Jean-Luc; Yurtalan, Muhammet; Otto, Martin R.; Lupascu, Adrian; Wilson, Christopher; Grifoni, Milena (2018-04-11)
      Article
      Accés obert
      Quantum two-level systems interacting with the surroundings are ubiquitous in nature. The interaction suppresses quantum coherence and forces the system towards a steady state. Such dissipative processes are captured by ...

    • Progress towards a unified approach to entanglement distribution 

      Streltsov, Alexander; Augusiak, Remigiusz; Demianowicz, Maciej; Lewenstein, Maciej (APS, 2015-07-30)
      Article
      Accés obert
      Entanglement distribution is key to the success of secure communication schemes based on quantum mechanics, and there is a strong need for an ultimate architecture able to overcome the limitations of recent proposals such ...

    • Propagation of collective modes in non-overlapping dipolar Bose-Einstein condensates 

      Gallemí Camacho, Alberto (Universitat Politècnica de Catalunya, 2013-07-19)
      Projecte Final de Màster Oficial
      Accés obert
      [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
      Accés obert
      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
      Accés obert
      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 Coherence and Quantum Correlations 

      Jiménez Machado, Gerard (Universitat Politècnica de Catalunya, 2017-07-09)
      Projecte Final de Màster Oficial
      Accés obert
      Realitzat a/amb:   Institut de Ciències Fotòniques (ICFO) / Universitat de Barcelona / Universitat Autònoma de Barcelona
      We demonstrate a new type of optical coherence tomography (OCT) scheme based on ideas put forward by Mandel's group in 1991, curiously the same year than the first OCT scheme was demonstrated. It involves the measurement ...

    • Quantum control of an ultracold quantum gas 

      Agustí Bruzon, Joan (Universitat Politècnica de Catalunya, 2019-09-09)
      Projecte Final de Màster Oficial
      Accés obert
      This thesis is devoted to the study of quantum control of an ultracold atomic ensemble of $^{87}$Rb. Stroboscopic probing is used to achieve real-time tracking of the collective spin magnitude and orientation via non-destructive ...

    • Quantum Control of Cold Atoms using microwaves 

      Martin Ciurana, Ferran (Universitat Politècnica de Catalunya, 2011-09-08)
      Projecte Final de Màster Oficial
      Accés obert
      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 droplets with particle imbalance in one-dimensional optical lattices 

      Vallès Muns, Jofre; Morera Navarro, Iván; Astrakharchik, Grigori; Julià Díaz, Bruno (2024-03-13)
      Article
      Accés obert
      We study the formation of particle-imbalanced quantum droplets in a one-dimensional optical lattice containing a binary bosonic mixture at zero temperature. To understand the effects of the imbalance from both the few- and ...

    • Quantum effects and gap morphology in the optical response of plasmonic gap-nanoantennas 

      Aguirregabiria Achutegui, Garikoitz (Universitat Politècnica de Catalunya, 2013-09-09)
      Projecte Final de Màster Oficial
      Accés obert
      [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 ...

    • Quantum limits of the resolution of imaging and lidar systems 

      Lamaison Vidarte, Miren (Universitat Politècnica de Catalunya, 2019-06)
      Treball Final de Grau
      Accés obert
      In this project we study the ultimate precision of a Lidar system aimed at estimating the position and velocity of a target with quantum light (entangled photons). By comparison, a standard Lidar system determines the ...

    • Quantum multiple hypothesis testing based on a sequential discarding scheme 

      Pérez Guijarro, Jordi; Pagès Zamora, Alba Maria; Rodríguez Fonollosa, Javier (Institute of Electrical and Electronics Engineers (IEEE), 2022-01-14)
      Article
      Accés obert
      We consider the quantum multiple hypothesis testing problem, focusing on the case of hypothesis represented by pure states. A sequential adaptive algorithm is derived and analyzed first. This strategy exhibits a decay rate ...

    • Quantum nonlinear optics using single atom 

      Bhattacharya, Arkabrata (Universitat Politècnica de Catalunya, 2012-09-10)
      Projecte Final de Màster Oficial
      Accés obert
      [ANGLÈS] In this thesis we tried to investigate the non-linear effects introduced by a generalized interaction of a two-level atom coupled to two photons. Scattering matrices were used to calculate the non-linear effects ...

    • Quantum photon correlations at the single atom level in free space 

      Goncalves Romeu, Daniel (Universitat Politècnica de Catalunya, 2019-08-31)
      Projecte Final de Màster Oficial
      Accés obert
      In this project, we present a novel approach to calculate and engineer the photon correlations emerging from the interference between an input field and the field scattered by an atom in free space. Historically, it has ...

    • Quantum random number generation based on the polarization dynamics of VCSELs 

      Mir Pou, Blanca (Universitat Politècnica de Catalunya, 2022-06)
      Treball Final de Grau
      Accés restringit per acord de confidencialitat
      Realitzat a/amb:   Quside
      Random numbers are essential in a great variety of applications ranging from stochastic simulations to secure communications. In this thesis, we report a technique for quantum random number generation based on the dynamics ...

    • Quantum simulation of non-trivial topology 

      Boada, Octavi; Celi, Alessio; Rodríguez-Laguna, Javier; Latorre, José I.; Lewenstein, Maciej (IOP, 2015-04-15)
      Article
      Accés obert
      We propose several designs to simulate quantum many-body systems in manifolds with a non-trivial topology. The key idea is to create a synthetic lattice combining real-space and internal degrees of freedom via a suitable ...

    • Quantum Technologies for Information Processing 

      Tura I Brugués, Jordi (Universitat Politècnica de Catalunya, 2011-07-27)
      Projecte/Treball Final de Carrera
      Accés obert
      English: Since its genesis, quantum mechanics has proved to be a very accurate model for predicting the behavior of the world below the nanoscale. However, crucial breakthroughs in technology were needed in order to be ...