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arXiv · 2512.17729

Fractionalized topological d+id superconductivity in the Yao-Lee-Kondo model

Chengzhi Tang·Hong Yao
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Abstract

A conclusive experimental realization of 2D chiral topological superconductivity remains elusive. Here we present a theoretical demonstration that a topological $d+id$ fractionalized superconducting phase (SC*) can emerge in the weak-coupling limit of a Kondo lattice model, where conduction electrons interact with a Yao-Lee spin liquid on the honeycomb lattice (the Yao-Lee-Kondo model). Using a renormalization-group analysis, we show that exchanging Majorana spinons from the Yao-Lee spin liquid generates effective interactions among the conduction electrons and drives a Cooper instability even for arbitrarily weak Kondo coupling. We further find that the induced leading inter-orbital antiferromagnetic interaction selects topological $d+id$ spin-singlet pairing with Chern number $C=\pm 2$. Meanwhile, the Majorana fermions in the Yao-Lee spin liquid remain gapless and deconfined in this regime, so the resulting state is a fractionalized topological $d+id$ superconductor (SC*). For sufficiently strong Kondo coupling, the system instead enters a heavy Fermi liquid phase with fractionalization (HFL*).

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Chengzhi Tang, Hong Yao. 2025-12-19. Fractionalized topological d+id superconductivity in the Yao-Lee-Kondo model. https://arxiv.org/abs/2512.17729

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