Magnetic ordering with an XY-like anisotropy in the honeycomb lattice iridates ZnIrO$_3$ and MgIrO$_3$ synthesized via a metathesis reaction

TL;DR

This study synthesizes and characterizes two novel honeycomb iridates, ZnIrO₃ and MgIrO₃, revealing their distinct magnetic behaviors and anisotropies, with implications for Kitaev physics and magnetic frustration.

Contribution

The paper reports the synthesis and detailed magnetic analysis of two new honeycomb iridates, highlighting their different magnetic ground states and anisotropic properties linked to Kitaev and Dzyaloshinskii-Moriya interactions.

Findings

ZnIrO₃ orders antiferromagnetically below 46.6 K

MgIrO₃ shows weak ferromagnetism below 31.8 K

Magnetic anisotropy indicates XY-like behavior

Abstract

We have successfully synthesized the novel antiferromagnets with Ir$^{4+}$ honeycomb lattice ZnIrO$_3$ and MgIrO$_3$ and investigated their magnetic and thermodynamic properties. The two iridates are isomorphic but exhibit qualitatively different magnetic properties. ZnIrO$_3$ shows antiferromagnetic ordering below 46.6 K, whereas MgIrO$_3$ displays weak ferromagnetic behavior below 31.8 K owing to formation of a canted antiferromagnetic ordering. The measurement of magnetic susceptibility with using an oriented powder sample revealed the presence of an XY-like magnetic anisotropy and a tilting magnetic structure which is possibly stabilized by the Kitaev interaction. Moreover, magnetization curves of MgIrO3 and ZnIrO3 up to 60 T show different behaviors, demonstrating that each magnetic ground state is different with each other. We discuss the difference in the ground state between MgIrO$_3$ and ZnIrO$_3$ from the viewpoint a magnetic model consisting of the Kitaev and Dzyaloshinskii-Moriya interactions with the spin frustration effect on the honeycomb lattice.