Designing Kitaev spin liquids in metal-organic frameworks

TL;DR

This paper proposes using metal-organic frameworks with Ru$^{3+}$ or Os$^{3+}$ ions to realize Kitaev spin liquids more accurately, leveraging MOFs' structural flexibility to suppress non-Kitaev interactions and explore various spin liquid states.

Contribution

It introduces MOFs as a new platform for realizing Kitaev spin liquids with suppressed non-Kitaev interactions, enabling exploration of diverse spin liquid phases.

Findings

MOFs can host honeycomb lattice structures with Ru$^{3+}$ or Os$^{3+}$ ions.

MOFs' flexibility allows design of three-dimensional lattices for different spin liquids.

Potential for experimental realization of Kitaev and Weyl spin liquids.

Abstract

Kitaev's honeycomb lattice spin model is a remarkable exactly solvable model, which has a particular type of spin liquid (Kitaev spin liquid) as the ground state. Although its possible realization in iridates and $\alpha$-RuCl$_3$ has been vigorously discussed recently, these materials have substantial non-Kitaev direct exchange interactions and do not have a spin liquid ground state. We propose metal-organic frameworks (MOFs) with Ru$^{3+}$ (or Os$^{3+}$) forming the honeycomb lattice as promising candidates for a more ideal realization of Kitaev-type spin models where the direct exchange interaction is strongly suppressed. The great flexibility of MOFs allows generalization to other three-dimensional lattices, for potential realization of a variety of spin liquids such as a Weyl spin liquid.