Prediction of Semimetallic Tetragonal Hf2O3 and Zr2O3 from First Principles

Tetragonal semimetallic phases are predicted for Hf2O3 and Zr2O3 using density functional theory. The structures belong to space group P (4) over tilde m2 and are more stable than their corundum counterparts. Many body corrections at first order confirm their semimetallic character. The carrier concentrations are very similar for both materials, and are estimated as 1.8 X 10(21) cm(-3) for both electrons and holes, allowing for electric conduction. This could serve as a basic explanation for the low resistance state of hafnia-based resistive random access memory. DOI: 10.1103/PhysRevLett.110.065502