Relating the Hall conductivity to the many-body Chern number using Fermi's Golden rule and Kramers-Kronig relations

Autor: Goldman, Nathan, Ozawa, Tomoki
Rok vydání: 2024
Předmět:
Zdroj: Comptes Rendus Physique 25, 289 (2024)
Druh dokumentu: Working Paper
DOI: 10.5802/crphys.191
Popis: This pedagogical piece provides a surprisingly simple demonstration that the quantized Hall conductivity of correlated insulators is given by the many-body Chern number, a topological invariant defined in the space of twisted boundary conditions. In contrast to conventional proofs, generally based on the Kubo formula, our approach entirely relies on combining Kramers-Kronig relations and Fermi's golden rule within a circular-dichroism framework. This pedagogical derivation illustrates how the Hall conductivity of correlated insulators can be determined by monitoring single-particle excitations upon a circular drive, a conceptually simple picture with direct implications for quantum-engineered systems, where excitation rates can be directly monitored.
Comment: 8 pages, 2 figures + Appendix
Databáze: arXiv