Measurement and modeling of propagation loss in semiconductor racetrack microresonators

Summary form only given. Semiconductor microring resonators fabricated using high-index-contrast waveguides offer promising potential for low-loss, compact wavelength selective devices. Since the intrinsic quality factor of the resonator is limited by propagation loss, measurement and modeling of the various loss mechanisms in the microcavity are of great practical interest. In this paper we report measurements and modeling method for the propagation loss in GaAs/AlGaAs racetrack resonators. Although the numerical results are applicable only to our devices, the methodology should apply to devices made elsewhere. The microcavities were fabricated using high-index-contrast waveguides. The tightly-confined waveguides allowed rings with radii as small as 2 /spl mu/m to be fabricated. A typical etched sidewall of the racetracks is shown.