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arXiv · 2102.12944

Spin-Polarized Fractional Corner Charges and Their Photonic Realization

Ran Gladstein Gladstone·Minwoo Jung·Gennady Shvets
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Abstract

We demonstrate that a spin degree of freedom can introduce additional texture to higher order topological insulators (HOTIs), manifesting itself in novel topological invariants, phases, and phase transitions. Spin-polarized mid-gap corner states of various multiplicities are predicted for different HOTI phases, and novel bulk-boundary correspondence principles are defined based on quantized bulk invariants such as total and spin corner charge. Those are shown to be robust with respect to symmetry-preserving spin-flipping perturbations. Photonic realizations of spin-linked topological phases are demonstrated in engineered systems with synthetically emulated spin degree of freedom.

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Ran Gladstein Gladstone, Minwoo Jung, Gennady Shvets. 2021-06-14. Spin-Polarized Fractional Corner Charges and Their Photonic Realization. https://doi.org/10.1103/physrevlett.128.026801

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