Anisotropic optical response of InAs/InP quantum dot avalanche photodiodes

摘要

Polarization resolved photocurrents in InAs/InP quantum dot (QD) avalanche photodiodes (APDs) comprising of three InAs QD layers have been determined under normal incidence. The responsivity of the InAs/InP APD from 1550 nm illumination was found to increase rapidly with increasing avalanche gain. Energy separation between the heavy-hole ground-state (hh1-e1) and heavy-hole excited-state (hh2-e2) absorptions was found to increase linearly with increasing applied electric field. The difference between the photocurrents corresponds to the hh1-e1 and hh2-e2 transitions, which increases exponentially after the onset of multiplication, suggesting the TE and TM polarization effects on the photoresponse of the InAs/InP APDs are amplified by the avalanche multiplication process.