Now showing items 41-53 of 53

  • Slow light enabled wavelength demultiplexing 

    Hayran, Zeki; Turduev, M.; Botey Cumella, Muriel; Herrero Simon, Ramon; Staliunas, Kestutis; Kurt, H. (Institute of Electrical and Electronics Engineers (IEEE), 2016)
    Conference report
    Open Access
    Photonic crystal waveguides supporting band gap guided modes hold great potential to tailor the group velocity of propagating light. We propose and explore different wavelength demultiplexer design approaches that ...
  • Spatial noise reduction in broad area semiconductors 

    Herrero Simon, Ramon; Botey Cumella, Muriel; Pradeep Kumar, Nikhil; Staliunas, Kestutis (IEEE, 2012)
    Conference report
    Restricted access - publisher's policy
  • 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 ...
  • Stabilization of broad area semiconductor lasers 

    Kumar, Shubham; Ahmed Waseem, Waqas Waseem; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2018)
    Conference report
    Restricted access - publisher's policy
    Broad Area Semiconductor edge-emitting lasers typically display self-focusing nonlinearity due to the refractive index dependence on the population inversion. It induces the homogeneous solution instability, multi-transverse ...
  • 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 laser sources by simultaneous index and pump modulations 

    Waseem Ahmed, Waqas; Kumar, Shubham; Medina Pardell, Judith; Botey Cumella, Muriel; Herrero Simon, Ramon; Staliunas, Kestutis (2018-06-01)
    Article
    Open Access
    We show that the emission of broad-area semiconductor amplifiers and lasers can be efficiently stabilized by introducing two-dimensional periodic modulations simultaneously on both the refractive index and the pump (gain–loss) ...
  • Stabilization of flat-mirror vertical-external-cavity surface-emitting lasers by spatiotemporal modulation of the pump profile 

    Ahmed Waseem, Waqas Waseem; Kumar, Shubham; Herrero Simon, Ramon; Botey Cumella, Muriel; Radziunas, Mindaugas; Staliunas, Kestutis (2015-10-20)
    Article
    Open Access
    We propose and demonstrate theoretically that vertical-external-cavity surface-emitting lasers (VECSELs) with external flat mirrors can be stabilized by applying a periodic spatiotemporal modulation of the pump current. ...
  • 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 ...
  • Suppression of modulation instability in broad area semiconductor amplifiers 

    Kumar, Shubham; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (2014-10-01)
    Article
    Restricted access - publisher's policy
    We show that a two-dimensional periodic modulation of the pump profile (modulation both along and perpendicular to the optical axis) can suppress the modulation instability in broad emission area semiconductor amplifiers. ...
  • Suppression of pattern-forming instabilities by genetic optimization 

    Kumar, Shubham; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (American Chemical Society (ACS), 2016-07-13)
    Article
    Restricted access - publisher's policy
  • Taming of modulation instability by spatio-temporal modulation of the potential 

    Kumar, Shubham; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (Macmillan Publishers, 2015-08-19)
    Article
    Open Access
    Spontaneous pattern formation in a variety of spatially extended nonlinear systems always occurs through a modulation instability, sometimes called Turing instability: the homogeneous state of the system becomes unstable ...
  • Tunable wavelength-demultiplexer by tapered photonic crystal waveguide 

    Hayran, Zeki; Turduev, Mirbek; Botey Cumella, Muriel; Herrero Simon, Ramon; Staliunas, Kestutis; Kurt, H. (Institute of Electrical and Electronics Engineers (IEEE), 2015)
    Conference report
    Open Access
    We numerically investigate the design of a wavelength de-multiplexer based on a tapered photonic crystal waveguide. The tapered waveguide is generated by reducing the width of the channel which, in turn, provides a gradual ...
  • Two-dimensional complex parity-time-symmetric photonic structures 

    Turduev, M.; Botey Cumella, Muriel; Giden, I.; Herrero Simon, Ramon; Kurt, H.; Ozbay, E; Staliunas, Kestutis (2015-02-20)
    Article
    Open Access
    We propose a simple realistic two-dimensional complex parity-time-symmetric photonic structure that is described by a non-Hermitian potential but possesses real-valued eigenvalues. The concept is developed from basic ...