Now showing items 1-20 of 44

  • 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 ...
  • Control of Q-factor in nanobeam cavities on substrate 

    Panettieri, Danilo; O'Faolain, Liam; Grande, Marco (IEEE, 2016-08-23) - Conference item
    In this paper, we demonstrate how to efficiently control the quality factor of silicon nitride nanobeam cavities, grown on a silica substrate and embedded in an upper cladding, by engineering the nanobeam cross-section and ...
  • 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 ...
  • Hybrid photonic crystal lasers 

    Liles, Alexandros A.; Bakoz, Andrei P.; Gonzalez-Fernandez, Alfredo; Habruseva, Tatiana; Persheyev, Saydulla; Huyet, Guillaume; Hegarty, Stephen P.; O'Faolain, Liam (IEEE, 2016-08-23) - Conference item
    Energy efficient Wavelength Division Multiplexing (WDM) is the key to satisfying the future bandwidth requirements of datacentres. As the silicon photonics platform is regarded the only technology able to meet the required ...