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

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 $\alpha {\text{-RuCl}}_3$.

11 pages, 4 figures

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Cited by in corpus (3)

• Disorder effects in the Kitaev-Heisenberg model
• Dynamics of fractionalized mean-field theories: consequences for Kitaev materials
• Disorder, Low-Energy Excitations, and Topology in the Kitaev Spin Liquid