Topological Quantum Spin Hall Semimetals with Light

Karyn Le Hur

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arXiv · 2412.07304

Topological Quantum Spin Hall Semimetals with Light

Karyn Le Hur

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Abstract

We introduce a quantum spin Hall semimetal or Fermi liquid characterized with a Z2 topological invariant, measurable through circularly polarized light. We propose its engineering through two topological metallic band structures in crystals on the honeycomb lattice, with spin-orbit interaction, realizable through the interplay of a charge or spin density wave substrate and Zeeman effects, in between a quantum spin Hall and a quantum anomalous Hall insulator. These systems show topologically protected helical edge or photo-induced currents.

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Karyn Le Hur. 2024-12-10. Topological Quantum Spin Hall Semimetals with Light. https://arxiv.org/abs/2412.07304

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