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arXiv · 2108.04320

Gapless excitations in non-Abelian Kitaev spin liquids with line defects

Lucas R. D. Freitas·Rodrigo G. Pereira
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Abstract

We show that line defects in a non-Abelian Kitaev spin liquid harbor gapless one-dimensional Majorana modes if the interaction across the defect falls below a critical value. Treating the weak interaction at the line defect within a mean-field approximation, we determine the critical interaction strength as a function of the external magnetic field. In the gapless regime, we use the low-energy effective field theory to calculate the spin-lattice relaxation rate for a nuclear spin near the defect and find a cubic temperature dependence that agrees with experiments in the Kitaev material $\alpha\text{-RuCl}_3$.

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Lucas R. D. Freitas, Rodrigo G. Pereira. 2021-08-09. Gapless excitations in non-Abelian Kitaev spin liquids with line defects. https://doi.org/10.1103/physrevb.105.l041104

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