Stabilization of a honeycomb lattice of IrO6 octahedra by formation of ilmenite-type superlattices in MnTiO3

Authors
Kei Miura, Kohei Fujiwara, Kei Nakayama, Ryo Ishikawa, Naoya Shibata, and Atsushi Tsukazaki

Abstract
In quantum spin liquid research, thin films are an attractive arena that enables the control of magnetic interactions via epitaxial strain and two-dimensionality, which are absent in bulk crystals. Here, as a promising candidate for the development of quantum spin liquids in thin films, we propose a robust ilmenite-type oxide with a honeycomb lattice of edge-sharing IrO₆ octahedra artificially stabilised by superlattice formation using the ilmenite-type antiferromagnetic oxide MnTiO₃. Stabilised sub-unit-cell-thick Mn–Ir–O layers are isostructural to MnTiO₃ and have an atomic arrangement corresponding to ilmenite-type MnIrO₃. By performing spin Hall magnetoresistance measurements, we observe that antiferromagnetic ordering in the ilmenite Mn sublattice is suppressed by modified magnetic interactions in the MnO₆ planes via the IrO₆ planes. These findings contribute to the development of two-dimensional Kitaev candidate materials, accelerating the discovery of exotic physics and applications specific to quantum spin liquids.

Communications Materials : https://www.nature.com/articles/s43246-020-00059-1