First-principle calculations of phononic, electronic and optical   properties of monolayer arsenene and antimonene allotropes
  Recently a stable monolayer of antimony in buckled honeycomb structure called antimonene was successfully grown on 3D topological insulator Bi$_2$Te$_3$ and Sb$_2$Te$_3$, which displays semiconducting properties. By first principle calculations, we systematically investigate the phononic, electronic and optical properties of $\alpha-$ and $\beta-$ allotropes of monolayer arsenene/antimonene. We investigate the dynamical stabilities of these four materials by considering the phonon dispersions. The obtained electronic structures reveal the direct band gap of monolayer $\alpha-$As/Sb and indirect band gap of $\beta-$As/Sb. Significant absorption is observed in $\alpha-$Sb, which can be used as a broad saturable absorber. 
Yuanfeng Xu, Bo Peng, Hao Zhang, Hezhu Shao, Rongjun Zhang, Hongliang   Lu, David Wei Zhang and Heyuan Zhu
cond-mat.mtrl-sci cond-mat.mes-hall