English

Hybrid d/p-wave altermagnetism in Ca$_{3}$Ru$_{2}$O$_{7}$ and strain-controlled spin splitting

Materials Science 2025-12-16 v3

Abstract

The interplay of strong electronic correlations, sizable octahedral distortions, and pronounced spin-orbit coupling (SOC) makes perovskite oxides promising candidates for realizing altermagnetic phases. We study altermagnetic phases in Ca3_3Ru2_2O7_7, a non-centrosymmetric layered perovskite whose ground state is a Kramers-degenerate antiferromagnet. We show that an alternative N\'eel-type spin arrangement hosts a P-2 d-wave altermagnetic state with orbital selectivity similar to Ca2_2RuO4_4. Including SOC generates a symmetry-allowed p-wave component and yields a hybrid d/p-wave altermagnetic order. We further demonstrate that biaxial strain tunes both magnetic stability and band splitting: compressive strain beyond 2 % favors the altermagnetic phase over the antiferromagnetic ground state, while tensile strain increases altermagnetic splittings by up to 9 %. To quantify these trends, we define an altermagnetic figure of merit and trace its strain dependence to changes in electronic localization and octahedral geometry in this polar metal.

Keywords

Cite

@article{arxiv.2504.04552,
  title  = {Hybrid d/p-wave altermagnetism in Ca$_{3}$Ru$_{2}$O$_{7}$ and strain-controlled spin splitting},
  author = {Andrea León and Carmine Autieri and Thomas Brumme and Jhon W. González},
  journal= {arXiv preprint arXiv:2504.04552},
  year   = {2025}
}

Comments

14 pages, 9 figures