Symmetry-Constrained Pairing and Finite-Momentum Superconductivity in Altermagnetic Systems
Symmetry-Constrained Pairing and Finite-Momentum Superconductivity in Altermagnetic Systems Juliet Zhong Independent Researcher | London, United Kingdom | July 2026 ORCID: 0009-0006-5099-3671 Abstract The interplay between magnetic order and superconductivity has long been understood through the lens of pair-breaking: magnetic exchange fields suppress Cooper pairing by splitting the degeneracy of time-reversed electronic states. Altermagnetism—a recently identified magnetic phase characterised by collinear spin order, zero net magnetisation, and momentum-dependent spin splitting arising from crystal symmetry—disrupts this conventional picture. Here we present a symmetry-constrained momentum-space analysis that reinterprets superconducting pairing in altermagnetic systems not as a competition between two antagonistic orders, but as a structural reorganisation of pairing channels governed by the underlying crystal symmetry, leading to a calculab...