Highly efficient optical filter based on vertically coupled photonic crystal cavity and bus waveguide

Abstract

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 coupled waveguide gives flexibility in the choice of the waveguide material and dimensions, dramatically lowering the insertion loss while achieving very high coupling efficiencies to wavelength scale resonators and thus allows the creation of PhC-based optical filters with very high extinction ratio (>10 dB).

Wavelength-controlled external-cavity laser with a silicon photonic crystal resonant reflector

“…The general design and working principle of the vertically coupled photonic crystal cavity and bus waveguide is detailed in [9]. A schematic of the system configuration presented in the figure 1a.…”

“…The present work demonstrates a novel EC laser design based on a low index waveguide coupled to a Photonic Crystal (PhC) cavity which is used as a resonant reflector [8,9]. This represents a step forward in the pursuit of laser architectures with small footprint, high Side-Mode Suppression Ratios, and high precision peak wavelength control, all of which are requirements for efficient WDM applications [5].…”

Toolkit for Photonic Integrated Circuits Based on Inverted Rib Waveguides

“…The details of the DA cavity design can be found in [20]. The cavity was realized in a triangular photonic crystal lattice of oxide holes with radius r=100nm and lattice constant a=390nm on a 220nm thick SOI.…”

Silicon photonic crystals: light emission, modulation and detection

“…Photonic crystal cavities are the strongest candidate for this purpose owing to their very high high Q/V values [15]. Photonic crystal cavities have been used to enhance the silicon light emission by utilizing its bandedge emission 6 .…”

“…Due to the smaller mode volume, the corresponding Fourier space distribution or k-space distribution expands and the problem of coupling reduces to that of matching the kspace of the waveguide (which is very localized) to that of a portion of the resonator's (which is expanded). With a suitably designed PhC cavity, a low effective index mode may thus be matched to that of a silicon based resonator 15 . This is a particularly powerful means of coupling a low index waveguide to a photonic crystal resonator.…”