A black phosphorus photo-detector for multispectral, high-resolution imaging

TL;DR

This paper demonstrates a black phosphorus-based photo-detector capable of high-contrast multispectral imaging in visible and infrared wavelengths, with sub-micron resolution, highlighting its potential for hyperspectral imaging applications.

Contribution

It introduces a multi-layer black phosphorus photo-detector capable of high-contrast multispectral imaging and high-resolution imaging in both visible and infrared regimes.

Findings

Achieved high-contrast images with V>0.9 in visible and infrared.

Mapped active area and characterized responsivity and gain.

Obtained diffraction-limited images with sub-micron resolution.

Abstract

Black phosphorus is a layered semiconductor that is intensely researched in view of applications in optoelectronics. In this Letter, we investigate a multi-layer black phosphorus photo-detector that is capable of acquiring high-contrast (V>0.9) images both in the visible ({\lambda}_{VIS}=532nm) as well as in the infrared ({\lambda}_{IR}=1550nm) spectral regime. In a first step, by using photocurrent microscopy, we map the active area of the device and we characterize responsivity and gain. In a second step, by deploying the black phosphorus device as a point-like detector in a confocal microsope setup, we acquire diffraction-limited optical images with sub-micron resolution. The results demonstrate the usefulness of black phosphorus as an optoelectronic material for hyperspectral imaging applications.