Now showing items 1-20 of 124

    • Ab initio dissipative solitons in an all-photonic crystal resonator 

      Etrich, C.; Iliew, R.; Staliunas, Kestutis; Lederer, Falk; Egorov, Oleg A. (2011-08-25)
      Article
      Open Access
      We identify dissipative solitons in a Kerr-nonlinear all-photonic crystal resonator by solving Maxwell’s equations directly. The photonic crystal allows for diffraction management, leading to solitons with unique properties. ...
    • Acoustically penetrable sonic crystals based on fluid-like scatterers 

      Cebrecos, A.; Romero García, Vicenç; Pico Vila, Rubén; Sánchez Morcillo, Victor José; Botey Cumella, Muriel; Herrero Simon, Ramon; Cheng, Yu Chieh; Staliunas, Kestutis (2015-01-21)
      Article
      Open Access
      We propose a periodic structure that behaves as a fluid-fluid composite for sound waves, where the building blocks are clusters of rigid scatterers. Such building-blocks are penetrable for acoustic waves, and their properties ...
    • All-dielectric self-cloaked structures 

      Hayran, Zeki; Kurt, H.; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (2018-03-17)
      Article
      Open Access
      A general procedure to design objects that are intrinsically invisible (without the necessity of an external cloak) has not been demonstrated so far. Here we propose a flexible method to design such self-cloaked objects ...
    • Angular filtering by Bragg photonic microstructures fabricated by physical vapour deposition 

      Grineviciute, Lina; Babayigit, Ceren; Gailevicius, Darius; Bor, Emre; Turduev, Mirbek; Purlys, Vytautas; Tolenis, Tomas; Kurt, Hamza; Staliunas, Kestutis (2019-07-01)
      Article
      Open Access
      We propose and experimentally demonstrate spatial filtering by photonic crystals in a Bragg configuration. Compared to the Laue configuration, where spatial filtering was already demonstrated before, the Bragg configuration ...
    • Asymmetric light transmission by using 2D PT-symmetric photonic nanostructure 

      Turduev, M.; Botey Cumella, Muriel; Herrero Simon, Ramon; Kurt, H.; Staliunas, Kestutis; Giden, I. (Wiley-IEEE Press, 2015)
      Conference report
      Restricted access - publisher's policy
      We propose for the first time a simple realization of a two-dimensional Parity-Time symmetric hexagonal shaped photonic structure composed of honeycomb lattice. The structure has a symmetric periodic modulation of the ...
    • Asymmetric light transmission effect based on an evolutionary optimized semi-Dirac cone dispersion photonic structure 

      Bor, Emre; Turduev, Mirbek; Yasa, Utku Görkem; Kurt, Hamza; Staliunas, Kestutis (American Physical Society (APS), 2018-12-10)
      Article
      Open Access
      In this paper, we present the numerical and experimental demonstration of asymmetric light transmission by a compact photonic crystal (PC) structure, which sustains semi-Dirac cone dispersion. The semi-Dirac point is ...
    • Asymmetric light transmission in PT-Symmetric microring resonators 

      Giden, I.; Dadashi, Kh.; Botey Cumella, Muriel; Herrero Simon, Ramon; Staliunas, Kestutis; Kurt, Hamza (2016-03-15)
      Article
      Restricted access - publisher's policy
      We propose a new type of add-drop microring resonator made of gain and loss materials. Microring resonators are compact, narrow band, and optical channel dropping filters. In such linear systems, light transmission to ...
    • Asymmetric transmission from a 2D PT-symmetric honeycomb nanostructure 

      Botey Cumella, Muriel; Herrero Simon, Ramon; Turduev, M.; Zhao, D.; Giden, I.; Kurt, H.; Staliunas, Kestutis (Institute of Electrical and Electronics Engineers (IEEE), 2014)
      Conference lecture
      Restricted access - publisher's policy
      We propose a simple realization of a 2-dimensonal (2D) PT-symmetric photonic structure: a honeycomb arrangement of alternating cylinders with gain or loss in a dielectric background. The structure provides a periodic ...
    • Axisymmetric photonic structures with PT-symmetry 

      Ahmed Waseem, Waqas Waseem; Herrero Simon, Ramon; Botey Cumella, Muriel; Staliunas, Kestutis (International Society for Photo-Optical Instrumentation Engineers (SPIE), 2016)
      Conference report
      Open Access
      PT-symmetric structures in photonic crystals, combining refractive index and gain-loss modulations is becoming a research field with increasing interest due to the light directionality induced by these particular potentials. ...
    • Beam focalization by chirped mirrors 

      Cheng, Yu Chieh; Peckus, Martynas; Kicas, Simonas; Trull Silvestre, José Francisco; Cojocaru, Crina; Vilaseca Alavedra, Ramon; Drazdys, Ramutis; Staliunas, Kestutis (Optical Society of American (OSA), 2014)
      Conference report
      Restricted access - confidentiality agreement
      A novel application of chirped dielectric mirrors for narrow beam focalization is proposed and demonstrated numerically and experimentally. Analogy to temporal dispersion compensation by chirped dielectric mirrors is discussed.
    • Beam focalization in reflection from flat dielectric subwavelength gratings 

      Cheng, Yu Chieh; Zeng, H; Trullàs Simó, Joaquim; Cojocaru, Crina; Malinauskas, Mangirdas; Jukna, T; Wiersma, D.S.; Staliunas, Kestutis (2014-10-15)
      Article
      Restricted access - publisher's policy
      We experimentally demonstrate the recently predicted effect of near-field focusing for light beams from flat dielectric subwavelength gratings (SWGs). This SWGs were designed for visible light 532 nm and fabricated by ...
    • Beam focusing in chirped mirror with a defect 

      Cheng, Yu Chieh; Staliunas, Kestutis (IEEE Press ; Wiley, 2004)
      Conference report
      Restricted access - publisher's policy
      Recently the beam focusing in reflection from chirped dielectric mirror has been proposed and demonstrated, where the negative (anomalous) diffraction is responsible for this flat mirror focusing. For a strong focusing ...
    • Beam focusing in reflections from flat subwavelength diffraction gratings 

      Cheng, Yu Chieh; Redondo, Javier; Staliunas, Kestutis (2014-03-10)
      Article
      Open Access
      We predict that narrow beams, reflecting from flat subwavelength diffraction gratings, can focus. The effect is shown for the beams of electromagnetic radiation; however, it should be observable for beams of waves of ...
    • Beam shaping in spatially modulated broad-area semiconductor amplifiers 

      Herrero Simon, Ramon; Botey Cumella, Muriel; Radziunas, Mindaugas; Staliunas, Kestutis (2012-12-15)
      Article
      Open Access
      We propose and analyze a beam-shaping mechanism that in broad-area semiconductor amplifiers occurs due to spatial pump modulation on a micrometer scale. The study, performed under realistic parameters and conditions, ...
    • 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; Garre Werner, Guillermo (2019-07-01)
      Article
      Open Access
      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 ...
    • 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 ...
    • Broadband third harmonic generation in quadratic media with disordered ferroelectric domains 

      Kalinowski, K.; Roppo, Vito; Wang, W.; Neshev, Dragomir N.; Kong, Y.; Cojocaru, Crina; Trull Silvestre, José Francisco; Vilaseca Alavedra, Ramon; Staliunas, Kestutis; Krolikowski, Wieslaw; Kivshar, Yu. (2010)
      Conference report
      Restricted access - publisher's policy
      We study nonlinear frequency generation in media with random ferroelectric domain structure. We show that randomness enables one to realize broadband third harmonic generation via cascading of two second order quasi-phase ...
    • Chiral modes in 2D PT-symmetric nanostructures 

      Botey Cumella, Muriel; Herrero Simon, Ramon; Turduev, M.; Kurt, H.; Staliunas, Kestutis (Springer International Publishing, 2015-11-15)
      Part of book or chapter of book
      Restricted access - publisher's policy
      We propose the stabilization of the output beam of Broad Area Semiconductor (BAS) amplifiers through the introduction of a spatially periodic modulated potential. We show that a periodic modulation of the pump profile in ...
    • Control and enhancement of beam quality of broadarea semiconductor devices and arrays by multimode interference couplers and two-dimensional gain modulation 

      Murad, M.; Sorel, M.; Herrero Simon, Ramon; Botey Cumella, Muriel; Marsh, J.H.; Staliunas, Kestutis (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Conference report
      Open Access
      It is proposed to control the beam quality of broad-area semiconductor devices by two-dimensional structuring enforcing phase coherence across the device. First results based on MMI couplers are presented.
    • Controllable light diffraction in woodpile photonic crystals filled with liquid crystal 

      Ho, Chih-Hua; Cheng, Yu Chieh; Maigyte, Lina; Zeng, H; Trull Silvestre, José Francisco; Cojocaru, Crina; Wiersma, D.S.; Staliunas, Kestutis (2015-01-12)
      Article
      Open Access
      An approach to switching between different patterns of light beams transmitted through the woodpile photonic crystals filled with liquid crystals is proposed. The phase transition between the nematic and isotropic liquid ...