BiAs as a novel 2D material

Finding two-dimensional semiconductors with large Rashba splitting is the vital step in the development of upcoming next generation spintronic technology as it assists the generation, detection and manipulation of spin current without magnetic field. Using first-principles calculations we find that BiAs is a stable layered semiconductors that crystalizes in a hexagonal honeycomb lattice geometry, with a narrow and indirect band gap. The inclusion of spin-orbit coupling in the calculations reveals the presence Rashba-Dresselhaus type spin splitting located around L-point of the Brillion zone, with an elliptical spin texture and Rashba energy E_R= 66 meV and coupling constant α_R = 4.32 eVÅ. We also studied BiAs in monolayer form, and find a direct band gap semiconductor with a circular spin texture around Γ point, and Rashba energy and coupling constant of  E_R = 17 meV and  α_R = 1.56 eVÅ, which are large spin-splittting parameter for a 2D material.  The effects of strain on the electronic structure of of the monolayer is also explored, and our results indicate that BiAs/AlN can potentially be used for the development novel field-effect transistors and spintronic devices.