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arXiv · 2312.12240

The pseudochiral Fermi surface of $\alpha$-RuI$_3$

Alex Louat·Matthew D. Watson·Timur K. Kim·Danrui Ni·Robert J. Cava·Cephise Cacho
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Abstract

In continuation of research into RuCl$_3$ and RuBr$_3$ as potential quantum spin liquids, a phase with unique magnetic order characterised by long-range quantum entanglement and fractionalised excitations, the compound RuI$_3$ has been recently synthesised. Here, we show RuI$_3$ is a moderately correlated metal with two bands crossing the Fermi level, implying the absence of any quantum spin liquids phase. We find that the Fermi surface as measured or calculated for a 2D ($k_\text{x},k_\text{y}$) slice at any $k_\text{z}$ lacks mirror symmetry, i.e. is pseudochiral. We link this phenomenon to the ABC stacking in the R$\bar{3}$ space group of $\alpha$-RuI$_3$, which is achiral but lacks any mirror or glide symmetries. We further provide a formal framework for understanding when such a pseudochiral electronic structure may be observed.

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Alex Louat, Matthew D. Watson, Timur K. Kim, Danrui Ni, Robert J. Cava, Cephise Cacho. 2023-12-19. The pseudochiral Fermi surface of $\alpha$-RuI$_3$. https://arxiv.org/abs/2312.12240

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