Magnetononlinear Hall effect from multigap topology in metal-organic frameworks

TL;DR

This paper demonstrates that non-Abelian multigap band topology with nontrivial Euler class invariants causes observable nonlinear Hall effects in tunable 2D metal-organic frameworks, linking topology to measurable transport phenomena.

Contribution

It reveals the presence of Euler class topology in metal-organic frameworks and connects it to observable nonlinear Hall effects in these materials.

Findings

Non-Abelian multigap topology induces nonlinear Hall effects.

External controls can tune the nonlinear response.

Euler class topology can be experimentally detected via magnetotransport.

Abstract

We unveil that non-Abelian multigap band topology characterized by nontrivial Euler class invariants induces observable magnetononlinear Hall transport phenomena. We demonstrate these effects in a highly-tunable class of recently synthesized two-dimensional kagome N-heterocyclic carbene (NHC) metal-organic frameworks. We showcase the controllability of the nonlinear effect upon applying external voltage, changing temperature, and chemical substitutions that preserve the bulk topology and associated edge states. Our findings therefore reveal an uncharted presence of Euler class topology in metal-organic materials that can be experimentally deduced through measurable magnetotransport.