We predict a quantum phase transition from normal to topological insulators in the 5d transition metal oxide Na2IrO3, where the transition can be driven by the change of the long-range hopping and trigonal crystal field terms. From the first-principles-derived tight-binding Hamiltonian we determine the phase boundary through the parity analysis. In addition, our first-principles calculations for Na2IrO3 model structures show that the interlayer distance can be an important parameter for the existence of a three-dimensional strong topological insulator phase. Na2IrO3 is suggested to be a candidate material which can have both a nontrivial topology of bands and strong electron correlations.
@article{arxiv.1201.5929,
title = {Topological Quantum Phase Transition in 5$d$ Transition Metal Oxide Na$_2$IrO$_3$},
author = {Choong H. Kim and Heung Sik Kim and Hogyun Jeong and Hosub Jin and Jaejun Yu},
journal= {arXiv preprint arXiv:1201.5929},
year = {2012}
}