Bethe ansatz solution of the topological Kondo model

Understand

Conduction electrons coupled to a mesoscopic superconducting island hosting Majorana bound states have been shown to display a topological Kondo effect with robust non-Fermi liquid correlations.

• With $M$ bound states coupled to $M$ leads, this is an SO($M$) Kondo problem, with the asymptotic high and low energy theories known from bosonization and conformal field theory studies.
• Here we complement these approaches by analyzing the Bethe ansatz equations describing the exact solution of these models at all energy scales.
• We apply our findings to obtain nonperturbative results on the thermodynamics of $M\rightarrow M-2$ crossovers induced by tunnel couplings between adjacent Majorana bound states.