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arXiv · 2407.00536

Unified picture of superconductivity and magnetism in CeRh$_2$As$_2$

Changhee Lee·Daniel F. Agterberg·P. M. R. Brydon
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Abstract

We study the micorscopic origin of the multiple superconducting and magnetic phases observed in CeRh$_2$As$_2$. We exploit the existence of a van Hove singularity enforced by the nonsymmorphic symmetry to conduct a renormalization group analysis. When Fermi-surface nesting is strong, we find two closely-competing superconducting states with opposite parities, as well as an instability towards specific spin-density wave states, consistent with key features of the phase diagram of CeRh$_2$As$_2$.

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Changhee Lee, Daniel F. Agterberg, P. M. R. Brydon. 2024-06-29. Unified picture of superconductivity and magnetism in CeRh$_2$As$_2$. https://doi.org/10.1103/dt7w-hh9f

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