The pseudochiral Fermi surface of α-RuI3

Abstract

Abstract In continuation of research into RuCl3 and RuBr3 as potential quantum spin liquids, a phase with unique magnetic order characterised by long-range quantum entanglement and fractionalised excitations, the compound RuI3 has been recently synthesised. Here, we show RuI3 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 x, k y) slice at any k z lacks mirror symmetry, i.e. is pseudochiral. We link this phenomenon to the ABC stacking in the R $$\bar{3}$$ 3 ¯ space group of α-RuI3, 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.