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Updated: Nov 15, 2025

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
New two-dimensional arsenene polymorph predicted by first-principles calculation: robust direct bandgap and enhanced
Yifan Gao1, Zixin Cheng2, Minru Wen1
1School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
Abstract:
In this work, we predict a new polymorph of 2D monolayer arsenic. This structure, namedδ-As, consists of a centrosymmetric monolayer, which is thermodynamically and kinetically stable. Distinctly different from the previously predicted monolayer arsenic with an indirect bandgap, the new allotrope exhibits a direct bandgap characteristic. Moreover, while keeping the direct bandgap unchanged, the bandgap of monolayerδ-As can be adjusted from 1.83 eV to 0 eV by applying zigzag-direction tensile strain, which is pronounced an advantage for solar cell and photodetector applications.
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