Thermal stability of pair density wave in a $d$-wave altermagnetic superconductor

Amrutha N Madhusuthanan; Madhuparna Karmakar

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arXiv · 2603.25314

Thermal stability of pair density wave in a $d$-wave altermagnetic superconductor

Amrutha N Madhusuthanan·Madhuparna Karmakar

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Abstract

We study finite-momentum superconductivity in a two-dimensional $d$-wave altermagnetic superconductor using a non-perturbative Monte Carlo approach beyond mean-field theory. We show that altermagnetism stabilizes a pair density wave (PDW) state without external magnetic fields and enables its survival at finite temperatures with robust phase coherence. Our results establish altermagnetism as a promising route to realizing thermally stable PDW superconductivity and identify clear thermodynamic and spectroscopic signatures.

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Amrutha N Madhusuthanan, Madhuparna Karmakar. 2026-03-26. Thermal stability of pair density wave in a $d$-wave altermagnetic superconductor. https://arxiv.org/abs/2603.25314

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