Honeycomb-structure RuI3, a new quantum material related to {\alpha}-RuCl3

TL;DR

This paper reports the synthesis of a new honeycomb-structured RuI3 polymorph with potential for quantum spin liquid behavior, characterized by metallicity, paramagnetism, and absence of magnetic order, offering a new platform for quantum material research.

Contribution

The discovery of a new RuI3 polymorph with a honeycomb lattice structure, synthesized under pressure and stable at ambient conditions, expanding the landscape of quantum materials.

Findings

Metallic and paramagnetic behavior observed

No long-range magnetic order down to 0.35 K

Large T-linear heat capacity contribution

Abstract

The Kitaev model predicts that quantum spin liquids (QSLs) will form at low temperatures under certain special conditions, and materials hosting the QSL state are frequently sought. The layered honeycomb lattice material {\alpha}-RuCl3 has emerged as a prime candidate for displaying the Kitaev QSL state. Here we describe a new polymorph of RuI3 with a layered honeycomb lattice structure, synthesized at moderately high pressures and stable under ambient conditions. Preliminary characterization reveals metallic, paramagnetic behavior, the absence of long-range magnetic order down to 0.35 K and an unusually large T-linear contribution to the heat capacity at low temperatures. We propose that this RuI3 phase, with a layered honeycomb lattice and strong spin-orbit coupling, provides a new route for the characterization of quantum materials.