Electrical Transport in the Hatsugai-Kohmoto Model

Daniele Guerci; Giorgio Sangiovanni; Andrew J. Millis; Michele Fabrizio

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arXiv · 2407.00156

Electrical Transport in the Hatsugai-Kohmoto Model

Daniele Guerci·Giorgio Sangiovanni·Andrew J. Millis·Michele Fabrizio

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Abstract

We show that in models with the Hatsugai-Kohmoto type of interaction that is local in momentum space thus infinite-range in real space, Kubo formulas neither reproduce the correct thermodynamic susceptibilities, nor yield sensible transport coefficients. Using Kohn's trick to differentiate between metals and insulators by threading a flux in a torus geometry, we uncover the striking property that Hatsugai-Kohmoto models with an interaction-induced gap in the spectrum sustain a current that grows as the linear size at any non-zero flux and which can be either diamagnetic or paramagnetic.

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Daniele Guerci, Giorgio Sangiovanni, Andrew J. Millis, Michele Fabrizio. 2024-06-28. Electrical Transport in the Hatsugai-Kohmoto Model. https://arxiv.org/abs/2407.00156

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