Zero Poisson's ratio in single-layer arsenic.

Zero (or near-zero) Poisson's ratio (ZPR) materials have important applications in the field of precision instruments because one of their faces is stable and will not be affected by strain. However, ZPR materials are extremely rare. Here, we report a novel ZPR material, two-dimensional 2/ arsenene, by first principles calculations. Its Poisson's ratio is -0.00021 (strain along zigzag direction), which is smaller than all the known near-zero Poisson's ratio crystal materials, and even 10 times smaller than Me-graphene (0.002). This feature makes it have huge potential applications in the field of precision instruments such as aviation, medicine, and flexible electronic devices. Besides, the band-gap range of 2/ arsenene is 1.420-2.154 eV (the corresponding wavelength is 873-575 nm) under strain from -5% to 5% along the zigzag direction, which is suitable for infrared and visible optoelectronic devices.