Topological insulators IV: Theory and Optics

11:30 am – 2:30 pm, Wednesday March 19 // Session MAR-M21 //Anaheim Convention Center, 254A (Level 2)

Chair:: Volodymyr Buturlim, Idaho National Laboratory
Topics:
Sponsored by: DCMP

Quantized responses in multigap topological phases

12:42 pm – 12:54 pm

Presenter: Wojciech J Jankowski (University of Cambridge)

Author: Robert-Jan Slager (Univ of Cambridge)

Quantized electromagnetic responses are rare smoking-gun probes constituting a hallmark for nontrivial topology in quantum materials. Following the discovery of the quantum Hall effect [1], it was shown that Chern insulators exhibit quantized bulk Hall currents [2], whereas Weyl semimetals can support quantized injection currents [3]. We show that certain three-dimensional multigap topological insulators can host quantized integrated shift photoconductivities due to bulk invariants defined under PT (spatiotemporal inversion) symmetry [4,5]. We recast the quantization in terms of quantum-geometric torsion tensors, connecting them to real Chern-Simons forms, and to virtual multiband optical transition amplitudes.

[1] K.V. Klitzing, et al., Phys. Rev. Lett. 45, 494–497 (1980).

[2] F. D. M. Haldane, Phys. Rev. Lett. 61 (2015).

[3] F. De Juan, et al., Nat. Commun. 8, 15995 (2017).

[4] W.J. Jankowski, et al., Phys. Rev. Lett. (accepted) [arXiv:2402.13245].

[5] W.J. Jankowski, et al., Phys. Rev. B 110, 075135 (2024).

PRESENTATIONS (15)