Highly sensitive and efficient 1550 nm photodetector for room temperature operation

TL;DR

This paper presents a novel 1550 nm photodetector using 2D semiconductor materials on a photonic crystal substrate, achieving high efficiency and ultra-low dark current at room temperature for quantum communication applications.

Contribution

The authors developed a 2D semiconductor-based photodetector with co-optimized dielectric photonic crystal substrate, enabling high EQE and low dark current at room temperature, suitable for single-photon detection.

Findings

Achieved >99% external quantum efficiency at 1550 nm

Reduced dark current by three orders of magnitude at room temperature

Demonstrated ~ps timing jitter and potential for large array integration

Abstract

Photonic quantum technologies such as effective quantum communication require room temperature (RT) operating single- or few- photon sensors with high external quantum efficiency (EQE) at 1550 nm wavelength. The leading class of devices in this segment is avalanche photodetectors operating particularly in the Geiger mode. Often the requirements for RT operation and for a high EQE are in conflict, resulting in a compromised solution. We have developed a device which employs a two-dimensional (2D) semiconductor material on a co-optimized dielectric photonic crystal substrate to simultaneously decrease the dark current by three orders of magnitude at RT and maintain an EQE of >99%. The device is amenable to avalanching and form a basis for single photon detection with ultra-low dark current and high photodetection efficiency. Harnessing the high carrier mobility of 2D materials, the device has ~ps jitter time and can be integrated into a large 2D array camera.