2020Advanced Functional Materials

Interlayer Transition in a vdW Heterostructure toward Ultrahigh Detectivity Shortwave Infrared Photodetectors

Tailei Qi, Youpin Gong, Alei Li, Xiaoming Ma, Peipei Wang, Rui Huang, Chang Liu, Ridwan Sakidja, Judy Z. Wu, Rui Chen, Liyuan Zhang

Advanced Functional Materials · 30, 1905687 (2020)

Read original paper

DOI 10.1002/adfm.201905687

**AI thematic illustration**Concept artwork created for this paper.

Introduction

A vertical GaTe/InSe junction responds at both 1064 and 1550 nm without cooling. The authors connect the extended wavelength range, beyond the individual layers' bandgap limits, to interlayer transitions enabled by type-II band alignment.

A closer reading

The junction offers more than the sum of two absorbers: states in different layers can support transitions at a new energy. Comparing the individual absorption edges with the junction's operating wavelengths is a direct way to follow that argument.