The topological property of SrRu2O6 and isostructural CaOs2O6 under various strain conditions is investigated using density functional theory. Based on an analysis of parity eigenvalues, we anticipate that a three-dimensional strong topological insulating state should be realized when band inversion is induced at the A point in the hexagonal Brillouin zone. For SrRu2O6, such a transition requires rather unrealistic tuning, where only the c axis is reduced while other structural parameters are unchanged. However, given the larger spin-orbit coupling and smaller lattice constants in CaOs2O6, the desired topological transition does occur under uniform compressive strain. Our study paves a way to realize a topological insulating state in a complex oxide, which has not been experimentally demonstrated so far.
@article{arxiv.1602.06243,
title = {Strain-induced topological transition in SrRu$_2$O$_6$ and CaOs$_2$O$_6$},
author = {Masayuki Ochi and Ryotaro Arita and Nandini Trivedi and Satoshi Okamoto},
journal= {arXiv preprint arXiv:1602.06243},
year = {2016}
}