High-speed InAs/GaSb Mid-Wave Infrared Interband Cascade Photodetector at Room Temperature

TL;DR

This paper presents a high-speed, room-temperature InAs/GaSb interband cascade photodetector with a 7.04 GHz bandwidth and low dark current, suitable for mid-infrared applications like LIDAR and spectroscopy.

Contribution

The work demonstrates a novel InAs/GaSb superlattice photodetector achieving high-speed operation and low noise at room temperature, with detailed RF performance analysis.

Findings

3-dB bandwidth up to 7.04 GHz

Dark current density around 9.39 x 10^-2 A/cm^2 at -0.1 V

Optical cut-off wavelength around 5 μm

Abstract

High speed mid-wave infrared (MWIR) photodetectors have important applications in the emerging areas such high-precision frequency comb spectroscopy and light detection and ranging (LIDAR). In this work, we report a high-speed room-temperature mid-wave infrared interband cascade photodetector (ICIP) based on a type-II InAs/GaSb superlattice. The devices show an optical cut-off wavelength around 5um and a 3-dB bandwidth up to 7.04 GHz. The relatively low dark current density around 9.39 x 10-2 A/cm2 under -0.1 V is also demonstrated at 300 K. These results validate the advantages of ICIPs to achieve both high-frequency operation and low noise at room temperature. Limitations on the high-speed performance of the detector are also discussed based on the S-parameter analysis and other RF performance measurement.