In-Plane Optical and Electrical Anisotropy of 2D Black Arsenic

Low-symmetry two-dimensional (2D) semiconductors have attracted great attention because of their rich in-plane anisotropic optical, electrical, and thermoelectric properties and potential applications in multifunctional nanoelectronic and optoelectronic devices. However, anisotropic 2D semiconductors with high performance are still very limited. Here, we report the systematic study of in-plane anisotropic properties in few-layered b-As that is a narrow-gap semiconductor, based on the experimental and theoretical investigations. According to experimental results, we have come up with a simple method for identifying the orientation of b-As crystals. Meanwhile, we show that the maximum mobility of electrons and holes was measured in the in-plane armchair (AC) direction. The measured maximum electron mobility ratio is about 2.68, and the hole mobility ratio is about 1.79.

Automated summary

This study systematically investigates the in-plane anisotropic properties of few-layered b-As, a narrow-gap semiconductor, and proposes a simple method for identifying crystal orientations. The research also reveals that the maximum mobility of electrons and holes is measured in the in-plane armchair direction.