Time response characteristics of an oxide-confined GaAs∕AlGaAs resonant cavity-enhanced photodetector

Abstract

This work compares the speed characteristics of a ∼135-μm-diam GaAs∕AlGaAs resonant cavity-enhanced (RCE) detector-emitter device with its laterally oxidized ∼80-μm-diam counterpart. The full width at half-maximum of the photocurrent spectrum exhibited no degradation in wavelength selectivity. Moreover, oxide confinement caused no current bottleneck that was inferred to adversely affect the device speed. The measured pulse responses were 65 and 75ps for the unoxidized and oxidized devices, respectively. Oxide-confined RCE photodetectors show relevant application in concentric hybrid RCE vertical cavity laser devices, this work deals with the speed characteristics of laterally oxidized resonant cavity-enhanced devices.