Anomalous flux state in higher-order topological superconductors

Yizhi You

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arXiv · 2301.04703

Anomalous flux state in higher-order topological superconductors

Yizhi You

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Abstract

We investigate the anomalous flux state of interacting higher-order topological superconductors (HOTSC) protected by rotation symmetries. By introducing a $\pi$ superconducting flux in 2D HOTSC, we demonstrate the existence of a robust zero mode trapped at the flux center. Remarkably, the rotation symmetry and fermion parity display projective representation inside the $\pi$ flux with $N=2$ supersymmetry algebra. A similar gapless flux pattern also exists in 3D HOTSCs, the flux lines of which carry anomalous helical modes that cannot be realized on purely one-dimensional lattice models. Notably, these exotic phenomena can be manifested in a 2D frustrated quantum magnet whose low energy excitation characterizes emergent Majoranas with HOTSC band structure and the $Z_2$ flux exhibiting supersymmetries.

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Yizhi You. 2023-01-11. Anomalous flux state in higher-order topological superconductors. https://arxiv.org/abs/2301.04703

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