Stability and Carrier Transport Properties of Phosphorene Based Polymorphic Nanoribbons.

A few-layer black phosphorene has recently gained significant interest in the scientific community. In this paper, we consider several polymorphs of phosphorene nanoribbons (PNRs) and employ deformation potential theory within the effective mass approximation together with density functional theory to investigate their structural, mechanical and electronic properties. The results show that stability of PNRs strongly depends on the direction along which they can be cut from 2D counterpart. PNRs also exhibit a wide range of line stiffness ranging from 6x10^10 eV/m to 18x10^11 eV/m which has little dependence on the edge passivation. Likewise, the calculated electronic properties of PNRs display them to be either narrow-gap semiconductor (Eg < 1 eV) or wide-gap semiconductor (Eg > 1 eV). The carrier mobility of PNRs is found to be comparable to that of the black phosphorene. Some of the PNRs show n-type (p-type) semiconducting character owing to their higher electron (hole) mobility. Passivation of the edges leads to n-type <-> p-type transition in many of the PNRs considered. The predicted novel characteristics of PNRs with a wide range of mechanical and electronic properties make PNRs to be potentially suitable for the use in nanoscale devices.