# Fredholm Homotopies for Strongly-Disordered 2D Insulators

@inproceedings{Bols2021FredholmHF, title={Fredholm Homotopies for Strongly-Disordered 2D Insulators}, author={Alex Bols and Jeffrey H. Schenker and Jacob Shapiro}, year={2021} }

We devise a method to interpolate between certain Fredholm operators arising in the context of strongly-disordered 2D topological insulators. We use this technique to prove the bulk-edge correspondence for mobility-gapped 2D topological insulators possessing a (Fermionic) time-reversal symmetry (class AII) and provide an alternative route to a theorem by Elgart-Graf-Schenker [13] about the bulk-edge correspondence for strongly-disordered integer quantum Hall systems.

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