Now showing items 1-12 of 322

  • Non-Hermitian broad aperture semiconductor lasers based on PT-symmetry 

    Botey Cumella, Muriel; Waseem Ahmed, Waqas; Medina Pardell, Judith; Herrero Simon, Ramon; Staliunas, Kestutis (2019)
    Conference report
    Open Access
    In this paper we propose a novel configuration to regularize the complex spatiotemporal dynamics of broad area lasers into bright light beam. It has recently been shown that arbitrary non-Hermitian optical potentials based ...
  • Defect reconstruction by non-destructive testing with laser induced ultrasonic detection 

    Mohamed Selim, Hossameldin; Delgado Prieto, Miquel; Trull Silvestre, José Francisco; Pico Vila, Rubén; Romeral Martínez, José Luis; Cojocaru, Crina (2020-02)
    Article
    Restricted access - publisher's policy
    This work envisages a detailed study of two-dimensional defect localization and reconstruction, using laser generated ultrasound and its application as a remotely controlled non-destructive testing method. As an alternative ...
  • Machine learning algorithms for predicting the amplitude of chaotic laser pulses 

    Amil Marletti, Pablo; Cornelles Soriano, Miguel; Masoller Alonso, Cristina (Institute of Physics (IOP), 2019-11-12)
    Article
    Restricted access - publisher's policy
    Forecasting the dynamics of chaotic systems from the analysis of their output signals is a challenging problem with applications in most fields of modern science. In this work, we use a laser model to compare the performance ...
  • Meta-mirrors with transverse invariance for beam shaping 

    Cheng, Yu-Chieh; Wang, Pei-Yu; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2019)
    Conference report
    Restricted access - publisher's policy
    The paper demonstrates spatial filtering in reflection based on meta-mirrors, composed of periodic subwavelength gratings. The periodic modulation of the refraction index on the sub-micron scale exhibits optical beam shaping ...
  • Gain-through-filtering enables tuneable frequency comb generation in passive optical resonators 

    Bessin, Florent; Perego, Auro M.; Staliunas, Kestutis; Turitsyn, Sergei K.; Kudlinski, Alexandre; Conforti, Matteo; Mussot, Arnaud (2019-10-03)
    Article
    Open Access
    Optical frequency combs (OFCs), consisting of a set of phase-locked, equally spaced laser frequency lines, have enabled a great leap in precision spectroscopy and metrology since seminal works of Hänsch et al. Nowadays, ...
  • Photonic crystal spatial filters fabricated by femtosecond pulsed Bessel beam 

    Gailevicius, Darius; Purlys, Vytautas; Staliunas, Kestutis (2019-10-15)
    Article
    Restricted access - publisher's policy
    We propose and experimentally demonstrate femtosecond direct laser writing with Bessel beams for the fabrication of photonic crystals with spatial filtering functionality. Such filters are mechanically stable, of small (of ...
  • Non-Hermitian Light Management Based on Local Hilbert Transform 

    Staliunas, Kestutis; Waseem Ahmed, Waqas; Botey Cumella, Muriel; Herrero Simon, Ramon (Institute of Electrical and Electronics Engineers (IEEE), 2019)
    Conference report
    Restricted access - publisher's policy
    Light patterns; Metamaterials; Non-Hermitian optics; Microlasers
  • Beam-combining scheme of high-power broad-area semiconductor lasers with Lyot-filtered reinjection: modeling, simulations, and experiments 

    Brée, Carsten; Raab, Volker; Montiel Ponsoda, Joan; Staliunas, Kestutis (2019-07-01)
    Article
    Restricted access - publisher's policy
    A brightness- and power-scalable polarization beam-combining scheme for high-power, broad-area semiconduc-tor laser diodes is investigated numerically and experimentally. To achieve the beam combining, we employ Lyot-filtered ...
  • Photonic crystal spatial filtering in broad aperture diode laser 

    Gawali, Sandeep Babu; Gailevicius, Darius; Garre Werner, Guillermo; Purlys, Vytautas; Cojocaru, Crina; Trull Silvestre, José Francisco; Montiel Ponsoda, Joan; Staliunas, Kestutis (2019-10-02)
    Article
    Restricted access - publisher's policy
    Broad aperture semiconductor lasers usually suffer from low spatial quality of the emitted beams. Due to the highly compact character of such lasers, the use of conventional intracavity spatial filters is problematic. We ...
  • Study of second and third harmonic generation from an indium tin oxide nanolayer: Influence of nonlocal effects and hot electrons 

    Rodríguez Suñé, Laura; Escalora, M.; Johnson, Allan; Cojocaru, Crina; Akozbek, Neset; Coppens, Zachary; Perez Salinas, Daniel; Wall, Simon; Trull Silvestre, José Francisco (2020-01-03)
    Article
    Open Access
    We report comparative experimental and theoretical studies of the second and third harmonic generation from a 20 nm-thick indium tin oxide layer in proximity of the epsilon-near-zero condition. Using a tunable optical ...
  • Phase locked harmonic generation in the opaque region of GaAs 

    Cojocaru, Crina; Rodríguez Suñé, Laura; Escalora, M.; Trull Silvestre, José Francisco (Institute of Electrical and Electronics Engineers (IEEE), 2019)
    Conference report
    Open Access
    We demonstrate second and third harmonic generation from a GaAs substrate, well-below the absorption edge, in both transmission and reflection geometries. The pump is tuned at 1064 nm, in the transparency range, while the ...
  • Structured Meta-Mirrors for Beam Spatial Filtering 

    Herrero Simon, Ramon; Wang, Pey-Yu; Botey Cumella, Muriel; Cheng, Yu-Chieh; Staliunas, Kestutis (Institute of Electrical and Electronics Engineers (IEEE), 2019)
    Conference report
    Open Access
    The work presents optical spatial filtering in reflection based on translationally invariant meta-mirrors. The meta-structure is generated by a thin grating presenting a transverse modulation of the refraction index on the ...