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arXiv · 2605.11669

Altermagnons at the metal-insulator transition

Jonas Issing·Matteo Dürrnagel·Sarbajit Mazumdar·Alena Lorenz·Niklas Witt·Giorgio Sangiovanni·Michael Klett·Lennart Klebl·Ronny Thomale·Jannis Seufert
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Abstract

By means of slave-boson theory for the Hubbard model on the checkerboard lattice, we calculate dynamical altermagnetic spin susceptibilities from the metallic to the Mott-insulating regime. We track magnon dispersion and lifetime renormalization, allowing us to uncover a crossover from a chirality-selective dissipation of magnon modes to coherent yet strongly deformed chiral magnon branches across the metal insulator transition. Our formalism lends itself to a quantitative description of collective spin dynamics in correlated altermagnets.

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Jonas Issing, Matteo Dürrnagel, Sarbajit Mazumdar, Alena Lorenz, Niklas Witt, Giorgio Sangiovanni, Michael Klett, Lennart Klebl, Ronny Thomale, Jannis Seufert. 2026-05-12. Altermagnons at the metal-insulator transition. https://arxiv.org/abs/2605.11669

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