Stabilization of a honeycomb lattice of IrO6 octahedra in superlattices with ilmenite-type MnTiO3
Abstract
In the quest for quantum spin liquids, thin films are expected to open the way for the control of intricate magnetic interactions in actual materials by exploiting epitaxial strain and two-dimensionality. However, materials compatible with conventional thin-film growth methods have largely remained undeveloped. As a promising candidate towards the materialization of quantum spin liquids in thin films, we here present a robust ilmenite-type oxide with a honeycomb lattice of edge-sharing IrO6 octahedra artificially stabilized by superlattice formation with an ilmenite-type antiferromagnetic oxide MnTiO3. The stabilized sub-unit-cell-thick Mn-Ir-O layer is isostructural to MnTiO3, having the atomic arrangement corresponding to ilmenite-type MnTiO3 not discovered yet. By spin Hall magnetoresistance measurements, we found that antiferromagnetic ordering in the ilmenite Mn sublattice is suppressed by modified magnetic interactions in the MnO6 planes via the IrO6 planes. These findings lay the foundation for the creation of two-dimensional Kitaev candidate materials, accelerating the discovery of exotic physics and applications specific to quantum spin liquids.