Local mixing in modified Becke-Johnson potential for low-dimensional systems

We propose an extension to the modified Becke-Johnson potential [1] that enables its use to study both heterogeneous and low-dimensional systems. This is achieved by using a coordinate-dependent expression for the c parameter, in contrast to the original global formulation. Our functional builds on the excellent description of bulk band gaps of the modified Becke-Johnson potential and preserves its modest computational effort. Furthermore, it yields with one single calculation band-diagrams and band-offsets of heterostructures, interfaces, and surfaces. We exemplify the usefulness and efficiency of our local functional by testing it for a series of semiconductor interfaces, surfaces, two-dimensional systems, and molecules.

[1] F. Tran and P. Blaha, Phys. Rev. Lett 102, 226401 (2009).