Now showing items 21-40 of 48

  • Fast monitoring of in-vivo conformational changes in myosin using single scan polarization- SHG microscopy 

    Psilodimitrakopoulos, Sotiris; Loza Álvarez, Pablo; Artigas García, David (2014-12-01)
    Article
    Restricted access - publisher's policy
    Fast imaging of molecular changes under high-resolution and label-free conditions are essential for understanding in-vivo processes, however, current techniques are not able to monitor such changes in real time. Polarization ...
  • Generation of multicolor spatial solitons with pulsed light 

    Carrasco Rodríguez, Sílvia; Pérez Torres, Juan; Artigas García, David; Torner Sabata, Lluís (2001-05)
    Article
    Restricted access - publisher's policy
    The impact of temporal effects to the generation of multiple wave quadratic spatial solitons with pulsed light is shown. We examine soliton formation under conditions of second-harmonic generation but our conclusions are ...
  • Imaging amylopectin's order in starch using 3-dimensional polarization SHG 

    Psilodimitrakopoulos, Sotiris; Amat Roldán, Iván; Artigas García, David; Loza Álvarez, Pablo (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2011)
    Conference report
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    In minimally destructive SHG biomedical imaging (high resolution optical slicing) is greatly desirable to extract the maximum of information from the light matter interaction. Here we develop a 3-D biophysical model and ...
  • La fotònica revoluciona les telecomunicacions 

    Torner Sabata, Lluís; Pérez Torres, Juan; Artigas García, David; Santos Blanco, M. Concepción (1998-12)
    Article
    Open Access
  • Las Telecomunicaciones fotónicas hacen posible super-internet 

    Torres, Juan P.; Torner Sabata, Lluís; Artigas García, David; Santos, María C. (Escola Tècnica Superior d'Enginyers de Telecomunicació de Barcelona, 1998)
    Article
    Open Access
  • Lossless directional guiding of light in dielectric nanosheets using Dyakonov surface waves 

    Takayama, Osamu; Artigas García, David; Torner Sabata, Lluís (2014-06-01)
    Article
    Restricted access - publisher's policy
    Guiding light at the nanoscale is usually accomplished using surface plasmons(1-12). However, plasmons propagating at the surface of a metal sustain propagation losses. A different type of surface excitation is the Dyakonov ...
  • Lost writing uncovered by laser two-photon fluorescence provides a terminus post quem for Roman colonization of Hispania Citerior 

    Cormack, I G; Loza-Álvarez, P; Sarrado, L; Tomás, S; Amat Roldán, Iván; Torner Sabata, Lluís; Artigas García, David; Guitart, Josep; Pera, J; Ros, J (Journal of Archeaological Science, 2007-10)
    Article
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    In this work, two-photon absorption fluorescence is used as a non-destructive method to detect the presence of paint upon an archaeological sample. The objective was to recover writing that, due to the discoloration caused ...
  • Measurement and correction of in vivo sample aberrations employing a nonlinear guide-star in two-photon excited fluorescence microscopy 

    Aviles Espinosa, Rodrigo; Andilla, Jordi; Porcar-Guezenec, Rafael; Olarte, Omar E.; Nieto, Marta; Levecq, Xavier; Artigas García, David; Loza Álvarez, Pablo (2011-11-01)
    Article
    Open Access
    We demonstrate that sample induced aberrations can be measured in a nonlinear microscope. This uses the fact that two-photon excited fluorescence naturally produces a localized point source inside the sample: the nonlinear ...
  • Nano guiding of light using Dyakonov waves 

    Takayama, Osamu; Torner Sabata, Lluís; Artigas García, David (2014-12)
    Article
    Restricted access - publisher's policy
    This special issue of Optics & Photonics News highlights the most exciting peer-reviewed optics research to have emerged over the past 12 months.
  • Nano Guiding of Light Using Dyakonov Waves 

    Takayama, Osamu; Artigas García, David; Torner Sabata, Lluís (OSA, 2014-12-01)
    Article
    Open Access
  • Nonlinear resonant conversion of modes in optical waveguides 

    Dios Otín, Víctor Federico; Shvartsburg, Alexander B.; Artigas García, David; Canal Bienzobas, Fernando (ELSEVIER SCIENCE BV, 1995-07-31)
    Article
    Open Access
    A new class of resonant exchange of power among three co-propagating modes in dielectric optical waveguides exhibiting Kerr-like nonlinearity is reported. Unlike the coupling of modes travelling in different, spatially ...
  • Observation of Dyakonov surface waves 

    Takayama, Osamu; Crasovan, I; Artigas García, David; Torner Sabata, Lluís (Institute of Electrical and Electronics Engineers (IEEE), 2009)
    Conference report
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    Summary form only given. A special type of surface wave was predicted by M. I. Dyakonov in 1988. Such waves exist under special conditions at the interface of transparent anisotropic materials, and hens they are lossless. ...
  • Observation of Dyakonov surface waves 

    Takayama, Osamu; Crasovan, L; Artigas García, David; Torner Sabata, Lluís (2009-01)
    Article
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    We report the first experimental observation of Dyakonov surface waves existing at the interface of transparent anisotropic crystals. A Otto-Kretchmann configuration was used to excite the surface waves at the interface ...
  • Optical Dyakonov surface waves at magnetic interfaces 

    Crasovan, L C; Artigas García, David; Mihalache, Dumitru; Torner Sabata, Lluís (2005-11)
    Article
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    We address the existence and properties of lossless surface waves that form at interfaces between magnetic and birefringent media. We show that the angular domain of existence of Dyakonov surface waves for magnetic interfaces ...
  • ORGANITZACIÓ DE LA PRODUCCIÓ (Examen 1r quadrimestre, 2n parcial) 

    Artigas García, David; Espot Piñol, Carmen; Borrell Matas, Marc (Universitat Politècnica de Catalunya, 2013-01-14)
    Exam
    Restricted access to the UPC academic community
  • Phase space description of nonlinear directional couplers 

    Artigas García, David; Dios Otín, Víctor Federico (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 1994-07-01)
    Article
    Open Access
    A comprehensive analysis of the symmetric nonlinear directional coupler as a function of the excitation conditions is reported. The analysis is based on a coupled-mode technique in normalized (dimensionless) parameters, ...
  • Phase space description of nonlinear directional couplers 

    Artigas García, David; Dios Otín, Víctor Federico (1994-07)
    Article
    Open Access
    A comprehensive analysis of the symmetric nonlinear directional coupler as a function of the excitation conditions is reported. The analysis is based on a coupled-mode technique in normalized (dimensionless) parameters, ...
  • Practical dyakonons 

    Takayama, Osamu; Artigas García, David; Torner Sabata, Lluís (2012-10-12)
    Article
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    We show that engineered photonic metamaterials composed of alternating layers of suitable dielectrics and metals can support different kinds of surface waves (SWs) under robust and readily achievable experimental conditions. ...
  • Pulse compression and gain enhancement in a DOPA based on aperiodically poled crystals 

    Artigas García, David; Reid, D T; Fejer, M M; Torner Sabata, Lluís (2002-03)
    Article
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    We describe theoretically a method of obtaining pulse compression and simultaneously improving amplification in a degenerate optical parametric amplifier by use of quasi-phase-matched engineered crystals. The scheme combines ...
  • Quadratic solitons: existence versus excitation 

    Carrasco Rodríguez, Sílvia; Torner Sabata, Lluís; Pérez Torres, Juan; Artigas García, David; López-Lago, E; Couderc, V; Barthelemy, A (2002-06)
    Article
    Restricted access - publisher's policy
    Whole families of stable optical solitons are known to exist in media with quadratic nonlinearity, and evidence of such existence has been demonstrated experimentally during the last years in several materials. However, ...