Binding of Non-Abelian Anyons to Vacancies in Kitaev's Spin Liquid on the Honeycomb Lattice

It was previously found that vacancies in the Z₂ spin liquid phase of Kitaev's honeycomb lattice model tend to bind a Z₂ magnetic flux. We find that this phenomenon extends also to the non-abelian spin liquid, where the bound Ising flux is associated with a non-abelian anyon. We show that this phenomenon occurs because a single vacancy is a resonant scatterer of quasiparticles, which therefore induces a sharp resonance peak in the low-energy local density of states. A bound flux effectively screens the vacancy and suppresses the resonance peak, thereby reducing the ground state energy. Because this result is obtained in the universal low-energy theory of the spin liquid it is independent of the special features of Kitaev’s exactly solvable model.