Metal-insulator transition and thermal scales in $d$-wave altermagnet

Santhosh Kannan; Jainam Savla; Madhuparna Karmakar

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arXiv · 2603.02707

Metal-insulator transition and thermal scales in $d$-wave altermagnet

Santhosh Kannan·Jainam Savla·Madhuparna Karmakar

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Abstract

We present the first finite-temperature study of a strongly correlated $d$-wave altermagnet across the Mott insulator-metal transition using a non-perturbative numerical approach. We map out the thermal phase diagram and provide quantitative estimates of the transition scales in an interacting altermagnet. We show that altermagnetism-induced geometric frustration stabilizes a finite-temperature correlated magnetic metal and enhances the magnetic transition scale across regimes of interaction. These results establish the finite-temperature landscape of correlated altermagnets and clarify the role of strong electronic interactions in this phase.

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Santhosh Kannan, Jainam Savla, Madhuparna Karmakar. 2026-03-03. Metal-insulator transition and thermal scales in $d$-wave altermagnet. https://arxiv.org/abs/2603.02707

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