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arXiv · 2410.02171

Topological superconductivity in a spin-orbit coupled Kondo lattice

Zekun Zhuang·Piers Coleman
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Abstract

We consider the effect of spin-orbit coupling on a two-dimensional Kondo Lattice model, in which conduction electrons are antiferromagnetically coupled to a Yao-Lee spin liquid. When a Rashba spin-orbit interaction and a nearest-neighbor Kondo interaction is introduced, the low-energy Majorana bands become gapped and develop Chern numbers, protecting unidirectionally propagating Majorana edge modes. Our model describes a chiral topological superconductor with fractionalized charge-$e$ order parameter and spontaneously broken time-reversal symmetry, which may be of interest for certain heavy fermion superconductors, such as UTe$_2$.

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Zekun Zhuang, Piers Coleman. 2024-10-03. Topological superconductivity in a spin-orbit coupled Kondo lattice. https://doi.org/10.1103/physrevb.110.235148

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