Inexorable Edge Kondo Breakdown in Topological Kondo Insulators

TL;DR

This paper uncovers a new type of Kondo breakdown in topological Kondo insulators, driven by symmetry-protected edge states, using quantum Monte Carlo simulations to demonstrate the destruction of Kondo screening.

Contribution

It introduces a novel mechanism of Kondo breakdown originating from symmetry-protected topological phases in interacting topological Kondo insulators.

Findings

Kondo screening is destroyed at edges or corners due to interactions.

Kondo breakdown is enforced by system symmetries.

Ground states are symmetry protected Haldane phases.

Abstract

Kondo breakdown is one of the most intriguing problems in strongly correlated electron systems, as it is rooted in many anomalous electron behaviors found in heavy-fermion materials. In Kondo lattice systems, Kondo breakdown can arise from either strong magnetic frustrations or critical fluctuations of collective modes. Here, we reveal a new type of Kondo breakdown with a fully different origin in interacting topological Kondo insulators. By employing numerically exact quantum Monte Carlo simulations, we show that with open boundary conditions, Kondo screening is inexorably destroyed by interaction effects on edges or corners in these systems. We argue that the Kondo breakdown is enforced by the symmetries of the system, because the ground states are symmetry protected Haldane phases.