Recent Submissions

  • Regularization of broad-area lasers by non-Hermitian potentials 

    Botey Cumella, Muriel; Ahmed, Waqas Waseem; Medina, Judith; Herrero Simon, Ramon; Wu, Ying; Staliunas, Kestutis (2019)
    Conference report
    Open Access
    It was recently shown that arbitrary non-Hermitian optical potentials based on local Parity-Time (PT-) symmetry may control the flow of light, due to the asymmetric mode coupling. We propose periodic non-Hermitian potentials ...
  • Methodology for lighting optimization applied to photocatalytic reactors 

    Tapia Tlatelpa, Tecilli; Trull Silvestre, José Francisco; Sala Caselles, Vicenç; Romeral Martínez, José Luis (Institute of Electrical and Electronics Engineers (IEEE), 2019)
    Conference lecture
    Open Access
    Replacement of conventional UV-lamps used in photocatalytic reactors by UV-LED sources with lower energy consumption and larger versatility has been proposed recently; However, the implementation of these types of sources ...
  • Surface and bulk harmonic generation in the opaque region of GaAs 

    Rodríguez Suñé, Laura; Trull Silvestre, José Francisco; Scalora, Michael; Cojocaru, Crina (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2019)
    Conference lecture
    Restricted access - publisher's policy
    We demonstrate second and third harmonic generation from a GaAs substrate, well-bellow the absorption edge, in both transmission and reflection geometries. The pump is tuned at 1064 nm, in the transparency range, while the ...
  • Brightness enhancement in Non-Hermintian VCSELs 

    Waseem Ahmed, Waqas; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (Optical Society of American (OSA), 2019)
    Conference report
    Restricted access - publisher's policy
    Vertical Cavity Surface Emitting lasers (VCSELs) are compact and efficient light sources useful for a variety of applications. However, due to lack of a transverse mode control mechanism, such lasers suffer from poor spatial ...
  • 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 ...
  • 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 ...
  • 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
  • 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 ...
  • Characterization of speckle patterns generated by a semiconductor laser with optical feedback for speckle reduction in retinal imaging instruments 

    Halpaap, Donatus; Tiana Alsina, Jordi; Vilaseca Ricart, Meritxell; Masoller Alonso, Cristina (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2019)
    Conference lecture
    Restricted access - publisher's policy
    We study experimentally the operating conditions of a semiconductor laser diode subjected to different amounts of optical feedback in order to find a stable and cost-efficient solution for speckle reduction in double-pass ...
  • Stabilization of Broad Area Semiconductor Laser Sources 

    Medina Pardell, Judith; Ahmed, W. W.; Kumar, Shubham; Botey Cumella, Muriel; Herrero Simon, Ramon; Staliunas, Kestutis (Institute of Electrical and Electronics Engineers (IEEE), 2018)
    Conference report
    Open Access
    We numerically proof the stabilization of broad area semiconductor laser sources by introducing simultaneous in-phase two-dimensional modulations on the refractive index and on the pump (gain). We also examine the interplay ...
  • Stabilization of Broad Area Semiconductor Amplifiers and Lasers by Double Modulation of Pump and Refractive Index 

    Ahmed, W. W.; Kumar, Shubham; Medina Pardell, Judith; Botey Cumella, Muriel; Herrero Simon, Ramon; Staliunas, Kestutis (Institute of Electrical and Electronics Engineers (IEEE), 2018)
    Conference report
    Restricted access - publisher's policy
    Broad Area Semiconductor Amplifiers and Lasers display instability of the homogeneous state typically related with self-focusing nonlinearities, inducing multi-transverse mode operation and filamentation that deteriorates ...

View more