Subwavelength silicon microcavities

Abstract

We present a study of the first silicon microdisk resonators which are smaller than the free-space resonant wavelength in all spatial dimensions. Spectral details of whispering gallery modes with azimuthal mode number m = 4-7 are measured in microdisks with diameters between 1.35 and 1.89microm and are studied at wavelengths from 1.52 to 1.62microm. For the structures considered here, m = 5 is the highest azimuthal mode order in a subwavelength cavity and has measured Q = 1250. These results agree well with theoretical calculations using a finite difference frequency domain method and fit an exponential scaling law relating Q to disk radius via m.

Dielectric microcavities: Model systems for wave chaos and non-Hermitian physics

“…This is in particular advantageous if the frequency dependence of the refractive index has to be included. For the frequency domain several approaches can be applied to quasi-two-dimensional geometries, such as the finite-difference frequency-domain (FDFD) method (Shainline et al, 2009), wave-matching method (Hentschel and Richter, 2002;Nöckel and Stone, 1995), internal scattering quantization approach (Tureci et al, 2005), volume element methods (Martin et al, 1999), boundary element methods (Wiersig, 2003a;Zou et al, 2011) and related methods based on boundary integral equations (Boriskina et al, 2004). The FDFD and the volume element methods are restricted to small structures because of the limited computational power that is available today.…”

Wavelength-sized Optomechanical Disk Resonator Embedded in a Sunflower Circular Photonic Crystal

“…This mode is identified from FDTD simulation as the whispering-gallery mode with radial and azimuthal number of (1,9). The optical Q is at least an order of magnitude higher than that of a bare disk with a similar size [6].…”

Silicon Photonics: A Review of Recent Literature

“…This year, a PhC cavity with Q>40,000 and very small mode volume was constructed by linking three point defects. Subwavelength silicon microcavities have been built and tested at telecomm wavelengths [46]. These are the first microdisks smaller than the free-space resonant wavelength in all spatial dimensions.…”