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arXiv · 1804.10212

Topological superconductivity in Kondo-Kitaev model

Wonjune Choi·Philipp W. Klein·Achim Rosch·Yong Baek Kim
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Abstract

We investigate possible topological superconductivity in the Kondo-Kitaev model on the honeycomb lattice, where the Kitaev spin liquid is coupled to conduction electrons via the Kondo coupling. We use the self-consistent Abrikosov-fermion mean-field theory to map out the phase diagram. Upon increasing the Kondo coupling, a first order transition occurs from the decoupled phase of spin liquid and conduction electrons to a ferromagnetic topological superconductor of Class D with a single chiral Majorana edge mode. This is followed by a second order transition into a paramagnetic topological superconductor of Class DIII with a single helical Majorana edge mode. These findings offer a novel route to topological superconductivity in the Kondo lattice system. We discuss the connection between topological nature of the Kitaev spin liquid and topological superconductors obtained in this model.

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Wonjune Choi, Philipp W. Klein, Achim Rosch, Yong Baek Kim. 2018-04-26. Topological superconductivity in Kondo-Kitaev model. https://doi.org/10.1103/physrevb.98.155123

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