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arXiv · 1910.09874

Novel chiral quantum spin liquids in Kitaev magnets

Arnaud Ralko·Jaime Merino
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Abstract

Mott insulators under sufficiently strong spin-orbit coupling can display quantum spin liquid phases with topological order and fractional excitations. Quantum magnets with pure Kitaev spin exchange interactions can host a gapped quantum spin liquid with a single Majorana edge mode propagating in the counter-clockwise direction when a small positive magnetic field is applied. Here, we show how under a sufficiently strong positive magnetic field a topological transition into a gapped quantum spin liquid with two Majorana edge modes propagating in the clockwise direction occurs. The Dzyaloshinskii-Moriya interaction is found to turn the non-chiral Kitaev's gapless quantum spin liquid into a chiral one with equal Berry phases at the two Dirac points. Thermal Hall conductance experiments can provide evidence of the novel topologically gapped quantum spin liquid states predicted.

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Arnaud Ralko, Jaime Merino. 2019-10-22. Novel chiral quantum spin liquids in Kitaev magnets. https://doi.org/10.1103/physrevlett.124.217203

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