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  • Letter
  • Open Access

From pure to mixed: Altermagnets as intrinsic symmetry-breaking indicators

Aline Ramires*,†

  • Laboratory for Theoretical and Computational Physics, PSI Center for Scientific Computing, Theory, and Data, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland

  • *Contact author: aline.ramires@tuwien.ac.at
  • †Present address: Institute of Solid State Physics, TU Wien, 1040 Wien, Austria.
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Phys. Rev. Research 8, L012025 – Published 26 January, 2026

DOI: https://doi.org/10.1103/jr65-4273

Abstract

We investigate the impact of the presence of altermagnetism on physical observables in the presence of explicit or spontaneous symmetry-breaking fields. We focus on unconventional superconductivity as a potential source of spontaneous symmetry-breaking fields and derive the symmetry considerations for the transmutation of altermagnets from pure to mixed, which can give rise to unusual phenomena. Based on this analysis, we put forward scenarios that could explain the apparent onset of time-reversal symmetry breaking at the superconducting critical temperature in Sr2RuO4, and the hidden magnetic phase and magnetic memory in 4Hb-TaS2.

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Outline

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Phys. Rev. Research 8, L012025– Published 26 January, 2026
  • Received 28 February 2025
  • Accepted 22 September 2025
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