Article

Compact highly-nonlinear AlGaAs waveguides for efficient wavelength conversion

Department of Electrical and Computer Engineering, University of Toronto, 10 King’s College Rd, Toronto, ON M5S 3G4, Canada.
Optics Express (Impact Factor: 3.53). 06/2011; 19(13):12440-55. DOI: 10.1364/OE.19.012440
Source: PubMed

ABSTRACT We report on the efficient nonlinear optical interactions in AlGaAs strip-loaded waveguides with a wafer composition specifically designed to increase the nonlinear coefficient. We demonstrate a broad-band self-phase modulation with a nonlinear phase shift up to 6π, and four-wave mixing with a 20-nm tuning range and signal-to-idler conversion efficiency up to 10 dB. Our samples are several times shorter than similar devices used for wavelength conversion by XPM and FWM in previous reports, but the efficiency of the observed effects is similar. Our experimental studies demonstrate the high potential of AlGaAs for all-optical networks.

Full-text

Available from: J. Stewart Aitchison, Sep 29, 2014
1 Follower
 · 
112 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: We present a side-by-side comparison of the nonlinear behavior of four passive AlGaAs ridge waveguides where the bandgap energy of the core layers ranges from 1.60 to 1.79 eV. By engineering the bandgap to suppress two-photon absorption, minimizing the linear loss, and minimizing the mode area, we achieve efficient wavelength conversion in the C-band via partially degenerate four-wave mixing with a continuous-wave pump. The observed conversion efficiency [Idler(OUT)/Signal(IN)=-6.8 dB] is among the highest reported in passive semiconductor or glass waveguides.
    Optics Letters 06/2014; 39(11):3161-4. DOI:10.1364/OL.39.003161 · 3.18 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Enhancements of the continuous-wave four-wave mixing conversion efficiency and bandwidth are accomplished through the application of plasma-assisted photoresist reflow to reduce the sidewall roughness of sub-square-micron-modal area waveguides. Nonlinear AlGaAs optical waveguides with a propagation loss of 0.56 dB/cm demonstrate continuous-wave four-wave mixing conversion efficiency of −7.8 dB. Narrow waveguides that are fabricated with engineered processing produce waveguides with uncoated sidewalls and anti-reflection coatings that show group velocity dispersion of +0.22 ps2/m. Waveguides that are 5-mm long demonstrate broadband four-wave mixing conversion efficiencies with a half-width 3-dB bandwidth of 63.8-nm.
    Optics Express 11/2014; 22(22). DOI:10.1364/OE.22.026814 · 3.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Harnessing nonlinear optical effects in a photonic chip scale has been proven useful for a number of key applications in optical communications. Microwave photonics (MWP) can also benefit from the adoption of such a technology, creating a new concept of nonlinear integrated MWP. Here, we look at the potential of using nonlinear optical effects in a chip scale to enable RF signal processing with enhanced performance. We review a number of recent results in this field, with particular focus on the creation of frequency agile and high suppression microwave bandstop filters using on-chip stimulated Brillouin scattering. We also discuss the future prospect of nonlinear integrated MWP to enable a general purpose, programmable analog signal processor, as well as compact, high performance active microwave filters with enhanced energy efficiency.
    Journal of Lightwave Technology 10/2014; 32(20):3421-3427. DOI:10.1109/JLT.2014.2306676 · 2.86 Impact Factor