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arXiv · 2603.17619

Polaron-mediated anisotropic exchange in 2D magnets

Johanna P. Carbone·Jakob Baumsteiger·Cesare Franchini
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Abstract

Two-dimensional (2D) magnets offer a rich platform for exploring emergent spin phenomena due to their unique and diverse magnetic properties. Beyond intrinsic magnetism, external manipulation$\unicode{x2013}$such as defect engineering, molecular adsorption, or charge doping$\unicode{x2013}$offers powerful routes to control their magnetic behavior. In this work, we demonstrate that localized electron polarons provide an effective means to modulate magnetism in 2D magnets. Using first-principles calculations, we investigate polaron formation in monolayer MnPS$_3$ and compute the resulting changes in magnetic exchange interactions. Our results reveal that polarons can locally break magnetic symmetry and induce anisotropic exchange couplings, highlighting a novel mechanism for tuning magnetic textures. This insight opens promising pathways for designing atomic-scale control of magnetism, with potential impact on spintronic technologies.

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Johanna P. Carbone, Jakob Baumsteiger, Cesare Franchini. 2026-03-18. Polaron-mediated anisotropic exchange in 2D magnets. https://arxiv.org/abs/2603.17619

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