Tight-binding model of rare-earth mono-pnictides

Rare-earth mono-pnictides, represented by ErAs, are compensated semimetals stable in the NaCl-type crystal structure at normal conditions. These pnictides have been integrated with conventional III-V semiconductors, forming thin epitaxial films or embedded nanoparticles. Possible applications of these pnictides include lattice matched epitaxial metal contacts to III-V semiconductors, thermoelectrics, and sources of terahertz radiation. Many of these rare earth pnictides are magnetic are low temperatures, and some are topological semimetals. Initially thought as semiconductors, the description of the electronic structure of rare-earth pnictides varies widely in the literature, depending on of the method employed, which include DFT-LDA/GGA, DFT+U, LDA+DMFT, and hybrid functionals. In this presentation we will describe a tight-binding parameterization of ErAs and GaAs aiming at describing the electronic structure of ErAs-GaAs containing a large number of atoms that is otherwise prohibitively large for first-principles calculations.