Opto-electrical and polarization performance of a mesa-structured InGaAs PIN detector integrated with subwavelength aluminum gratings
Junyang Zhang, Zhendong Gao, Miao Wang, Guojian Ding, Chunhua Du, Yang Jiang, Haiqiang Jia, Wenxin Wang, Hong Chen, Zhen Deng
Abstract
Polarization detection in the short-wave infrared (SWIR) region presents broad applications in target-background contrast enhancement, underwater imaging, material classification, etc. A mesa structure can prevent electrical cross talk due to its intrinsic advantages, making it potentially suited to meet the need for manufacturing smaller-sized devices to save cost and shrink volume. In this Letter, mesa-structured InGaAs PIN detectors with a spectral response ranging from 900 nm to 1700 nm and a detectivity of 6.28 × 10 11 cm·Hz 1/2 /W at 1550 nm and –0.1 V bias (room temperature) have been demonstrated. Furthermore, the devices with subwavelength gratings in four orientations show obvious polarization performance. Their extinction ratios (ERs) can reach 18:1 at 1550 nm and their transmittances are over 90%. Such a polarized device with a mesa structure could realize miniaturized SWIR polarization detection.