Electronic Transport Properties of Janus Ge-Based Two-Dimensional IV−V Monolayer

Two-dimensional (2D) semiconductors with anisotropic properties have garnered significant attention in materials research, particularly those exhibiting strong anisotropy in carrier mobility. A captivating subset of these materials is Janus monolayers, characterized by the substitution of all atoms on one side of their binary counterpart with a different element. This structural transformation disrupts the out-of-plane mirror symmetry, offering a platform for exploring extraordinary physical properties in 2D Janus crystals. In this study, we present a comprehensive exploration of the electronic transport properties of a Janus Ge-based 2D IV−V monolayer. Our investigation employs density functional theory in conjunction with the non-equilibrium Green's function approach. To characterize the current-voltage (I-V) characteristics of the monolayer, we establish a two-probe system with the intrinsic 2D monolayer serving as the channel and doped monolayer as electrodes. We systematically investigated the effect of the doping concentration of the probes and channel length on the transport properties. Our results demonstrate that this Janus monolayer displays unique transport characteristics, including a direct bandgap and carrier mobility that depend on the lattice direction, indicating anisotropic transport behavior. These unique characteristics, stemming from the Janus architecture, position the monolayer as a promising candidate for applications in the field of nanoelectronics.