High-Sensitivity Two-Photon Absorption Microcavity Autocorrelator

Abstract

A GaAs-AlAs microcavity device has been used as a photodetector in an autocorrelator for measuring the temporal pulsewidth of 1.5-μm optical pulses. Enhancement of the two-photon absorption photocurrent due to the microcavity structure results in an autocorrelation (average power times peak power) sensitivity of 9.3×10/sup -4/ (mW) <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> , which represents two orders of magnitude improvement when compared with conventional autocorrelators.