Kitaev Spin Liquid Candidate OsxCl3 Comprised of Honeycomb Nano-Domains

TL;DR

This study synthesizes and characterizes OsxCl3, revealing nano-domains with honeycomb structures and signs of potential Kitaev spin liquid behavior, despite lattice imperfections.

Contribution

It uncovers nano-scale honeycomb domains in OsxCl3 and suggests possible Kitaev spin liquid characteristics in a material with structural disorder.

Findings

Nano-domains with honeycomb lattice observed

No magnetic long-range order down to 0.08 K

Broad heat capacity peak at 0.15 K indicating short-range order

Abstract

An osmium chloride with the chemical formula of OsxCl3 (x = 0.81) was synthesized and its crystal structure and thermodynamic properties were investigated. OsxCl3 crystallizes in a layered CdCl2-type structure with the triangular lattice partially occupied by Os ions on average. However, on microscopic length scales, the triangular lattice is composed of nano-domains with a honeycomb arrangement of Os ions, as observed by electron microscopy and Raman scattering experiments. Magnetization and heat capacity measurements revealed an absence of magnetic long-range order down to 0.08 K, while a broad peak in heat capacity at 0.15 K may indicate a short-range order in the local honeycomb lattice. OsxCl3 may exhibit certain aspects of the Kitaev spin liquid that are expected for a perfect honeycomb lattice of osmium trichloride.