Now showing items 1-20 of 40

  • Cascaded modulator architecture for WDM applications 

    Debnath, Kapil; O'Faolain, Liam; Gardes, Frederic Y.; Steffan, Andreas G.; Reed, Graham T.; Krauss, Thomas F. (2012-12-03) - Journal article
    Integration density, channel scalability, low switching energy and low insertion loss are the major prerequisites for on-chip WDM systems. A number of device geometries have already been demonstrated that fulfill these ...
  • Coherent control of plasmonic nanoantennas using optical eigenmodes 

    Kosmeier, Sebastian; De Luca, Anna Chiara; Zolotovskaya, Svetlana; Di Falco, Andrea; Dholakia, Kishan; Mazilu, Michael (2013-05-09) - Journal article
    The last decade has seen subwavelength focusing of the electromagnetic field in the proximity of nanoplasmonic structures with various designs. However, a shared issue is the spatial confinement of the field, which is ...
  • Deliberate versus intrinsic disorder in photonic crystal nanocavities investigated by resonant light scattering 

    Portalupi, S. L.; Galli, M.; Belotti, M.; Andreani, L. C.; Krauss, Thomas Fraser; O'Faolain, Liam (2011-07-12) - Journal article
    We report a study of photonic crystal nanocavities as a function of lattice disorder, which is implemented by deliberate radius variations of the holes forming the photonic crystal. Using cross-polarized laser light ...
  • Dielectric waveguide vertically coupled to all-silicon photodiodes operating at telecommunication wavelengths 

    Debnath, Kapil; Gardes, Frederic Y.; Knights, Andrew P.; Reed, Graham T.; Krauss, Thomas F.; O'Faolain, Liam (2013-04) - Journal article
    We present a method for detecting light in the 1550 nm wavelength window based on a silicon nitride waveguide that is vertically coupled to a silicon photonic crystal cavity. The absorption in silicon arises from deep-levels ...
  • Efficient slow-light coupling in a photonic crystal waveguide without transition region 

    White, T. P.; Botten, L. C.; de Sterke, C. Martijn; Dossou, K. B.; McPhedran, R. C. (2008-11-15) - Journal article
    We consider the coupling into a slow mode that appears near an inflection point in the band structure of a photonic crystal waveguide. Remarkably, the coupling into this slow mode, which has a group index n(g) > 1000, can ...
  • Electrical conduction and optical properties of doped SOI Photonic Crystals 

    Cardile, Paolo; Franzo, Giorgia; Lo Savio, Roberto; Galli, Matteo; Krauss, Thomas Fraser; Priolo, Francesco; O'Faolain, Liam (2011-05) - Journal article
    We investigate the electrical properties of silicon-on-insulator (SOI) photonic crystals as a function of both doping level and air filling factor. The resistance trends can be clearly explained by the presence of a depletion ...
  • Enhanced 1.54 mu m emission in Y-Er disilicate thin films on silicon photonic crystal cavities 

    Lo Savio, R.; Miritello, M.; Shakoor, A.; Cardile, P.; Welna, K.; Andreani, L. C.; Gerace, D.; Krauss, T. F.; O'Faolain, L.; Priolo, F.; Galli, M. (2013-04-22) - Journal article
    We introduce an Y-Er disilicate thin film deposited on top of a silicon photonic crystal cavity as a gain medium for active silicon photonic devices. Using photoluminescence analysis, we demonstrate that Er luminescence ...
  • Evidence of guided resonances in photonic quasicrystal slabs 

    Ricciardi, Armando; Pisco, Marco; Cutolo, Antonello; Cusano, Andrea; O'Faolain, Liam; Krauss, Thomas F.; Castaldi, Giuseppe; Galdi, Vincenzo (2011-08-29) - Journal article
    We report on the experimental evidence of Fano-type guided resonances (GRs) in aperiodically-ordered photonic quasicrystal slabs. With specific reference to the Ammann-Beenker (8-fold symmetric, quasiperiodic) octagonal ...
  • Experimental evidence of guided-resonances in photonic crystals with aperiodically ordered supercells 

    Ricciardi, Armando; Pisco, Marco; Gallina, Ilaria; Campopiano, Stefania; Galdi, Vincenzo; O'Faolain, Liam; Krauss, Thomas F.; Cusano, Andrea (2010-12-01) - Journal article
    We report on the first experimental evidence of guided resonances (GRs) in photonic crystal slabs based on aperiodically ordered supercells. Using Ammann-Beenker (quasiperiodic, eightfold symmetric) tiling geometry, we ...
  • Extraction of group index of lossy photonic crystal waveguides 

    Debnath, Amrita; Debnath, Kapil; O'Faolain, Liam (2015-01-15) - Journal article
    We present a numerical approach to extract group index in photonic crystal (PhC) waveguides using two- and three-dimensional finite-difference time-domain methods and make a quantitative study of the effects of loss on ...
  • Fabrication of low loss dispersion engineered chalcogenide photonic crystals 

    Spurny, Marcel; O'Faolain, Liam; Bulla, Douglas A. P.; Luther-Davies, Barry; Krauss, Thomas F. (2011-01-31) - Journal article
    We demonstrate low loss photonic crystal waveguides in chalcogenide (Ge33As12Se55) glasses. The measured losses are as low as 21dB/cm. We experimentally determine the refractive index of the thin film chalcogenide glass ...
  • Flexible metamaterials at visible wavelengths 

    Di Falco, Andrea; Ploschner, Martin; Krauss, Thomas F. (2010-11-04) - Journal article
    We report on the fabrication and characterization of plasmonic structures on flexible substrates (Metaflex) and demonstrate the optical properties of a single layer of Metaflex. The layer exhibits a plasmonic resonance in ...
  • Focusing with planar microlenses made of two-dimensionally varying high contrast gratings 

    Klemm, A.B.; Stellinga, D.; Martins, E.R.; Lewis, L.; O'Faolain, L.; Krauss, T.F. (2014-09-11) - Journal article
    We report on the focusing performance of reflective two-dimensionally varying high contrast grating lenses based on silicon. The combination of their subwavelength nature and their high refractive index contrast makes it ...
  • Four-wave mixing in photonic crystal waveguides : slow light enhancement and limitations 

    Li, Juntao; O'Faolain, Liam; Rey, Isabella Helen; Krauss, Thomas Fraser (2011-02-28) - Journal article
    We demonstrate continuous wave four-wave mixing in silicon photonic crystal waveguides of 396 mu m length with a group index of n(g) = 30. The highest observed conversion efficiency is -24 dB for 90 mW coupled input pump ...
  • Four-wave mixing in slow light photonic crystal waveguides with very high group index 

    Li, Juntao; O'Faolain, Liam; Krauss, Thomas F. (2012-07-30) - Journal article
    We report efficient four-wave mixing in dispersion engineered slow light silicon photonic crystal waveguides with a flat band group index of n(g) = 60. Using only 15 mW continuous wave coupled input power, we observe a ...
  • Four-zone reflective polarization conversion plate 

    Nalimov, A.G.; Stafeev, S.S.; O'Faolain, L.; Kotlyar, V.V. (SPIE-The International Society for Optical Engineering, 2014-09-23) - Book item
    Binary diffraction optical element was designed for polarization conversion from linear to radial. A grating period was equal to 400 nm, a relief height was equal to 110 nm. Simulation by FDTD method and Rayleight-Zommerfeld ...
  • Highly efficient coupling between a monolithically integrated photonic crystal cavity and a bus waveguide 

    Debnath, Kapil; Welna, Karl Peter; Ferrera, Marcello; Deasy, Kieran; Lidzey, David; Krauss, Thomas Fraser; O'Faolain, Liam (SPIE, 2012-01-30) - Conference item
    We experimentally demonstrate a new optical filter design comprising of a photonic crystal cavity and a low index bus waveguide which are monolithically integrated on a silicon-on-insulator (SOI) platform. We have fabricated ...
  • Highly efficient optical filter based on vertically coupled photonic crystal cavity and bus waveguide 

    Debnath, Kapil; Welna, Karl; Ferrera, Marcello; Deasy, Kieran; Lidzey, David G.; O'Faolain, Liam (2013-01-15) - Journal article
    We experimentally demonstrate a new optical filter design based on a vertically coupled photonic crystal (PhC) cavity and a bus waveguide monolithically integrated on the silicon-on-insulator platform. The use of a vertically ...
  • Hydrogen induced optically-active defects in silicon photonic nanocavities 

    Boninelli, S.; Franzo, G.; Cardile, P.; Priolo, F.; Lo Savio, R.; Galli, M.; Shakoor, A.; O'Faolain, L.; Krauss, T. F.; Vines, L.; Svensson, B. G. (2014-04-21) - Journal article
    We demonstrate intense room temperature photoluminescence (PL) from optically active hydrogen- related defects incorporated into crystalline silicon. Hydrogen was incorporated into the device layer of a silicon on insulator ...
  • Indirect transitions of a signal interacting with a moving refractive index front 

    Munoz, Michel Castellanos; Petrov, Alexander Yu; O'Faolain, Liam; Li, Juntao; Krauss, Thomas F.; Eich, Manfred (SPIE-The International Society for Optical Engineering, 2014) - Conference item
    The dynamic manipulation of light can be achieved by the interaction of a signal pulse propagating through or reflected from a refractive index front. Both the frequency and the wave vector of the signal are changed in ...