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arXiv · 2201.06085

Metastable Kitaev Magnets

Faranak Bahrami·Mykola Abramchuk·Oleg I. Lebedev·Fazel Tafti
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Abstract

Nearly two decades ago, Alexei Kitaev proposed a model for spin-$1/2$ particles with bond-directional interactions on a two-dimensional honeycomb lattice which had the potential to host a quantum spin-liquid ground state. This work initiated numerous investigations to design and synthesize materials that would physically realize the Kitaev Hamiltonian. The first-generation of such materials, such as Na$_{2}$IrO$_{3}$, $\alpha$-Li$_{2}$IrO$_{3}$, and $\alpha$-RuCl$_{3}$, revealed the presence of non-Kitaev interactions such as the Heisenberg and off-diagonal exchange. Both physical pressure and chemical doping were used to tune the relative strength of the Kitaev and competing interactions; however, little progress was made towards achieving a purely Kitaev system. Here, we review the recent breakthrough in modifying Kitaev magnets via topochemical methods that has led to the second-generation of Kitaev materials. We show how structural modifications due to the topotactic exchange reactions can alter the magnetic interactions in favor of a quantum spin-liquid phase.

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Faranak Bahrami, Mykola Abramchuk, Oleg I. Lebedev, Fazel Tafti. 2022-01-16. Metastable Kitaev Magnets. https://arxiv.org/abs/2201.06085

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