Zero-field finite-momentum and field-induced superconductivity in altermagnets

Debmalya Chakraborty; Annica M. Black-Schaffer

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arXiv · 2309.14427

Zero-field finite-momentum and field-induced superconductivity in altermagnets

Debmalya Chakraborty·Annica M. Black-Schaffer

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Abstract

We explore the possibilities for spin-singlet superconductivity in newly discovered altermagnets. Investigating $d$-wave altermagnets, we show that finite-momentum superconductivity can easily emerge in altermagnets even though they have no net magnetization, when the superconducting order parameter also has $d$-wave symmetry with nodes coinciding with the altermagnet nodes. Additionally, we find a rich phase diagram when both altermagnetism and an external magnetic field are considered, including superconductivity appearing at high magnetic fields from a parent zero-field normal state.

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Debmalya Chakraborty, Annica M. Black-Schaffer. 2023-09-25. Zero-field finite-momentum and field-induced superconductivity in altermagnets. https://arxiv.org/abs/2309.14427

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