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arXiv · 2408.07747

Perfect superconducting diode effect in altermagnets

Debmalya Chakraborty·Annica M. Black-Schaffer
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Abstract

We investigate intrinsic superconducting diode effect in the unconventional superconducting state of $d$-wave altermagnets. We find large diode efficiencies in the wide-reaching finite-momentum pairing regimes of the phase diagram. Remarkably, even perfect diode efficiency of 100% can be obtained in the presence of an external magnetic field. We attribute the largest efficiencies to competition between multiple zero-momentum (BCS) and finite-momentum superconducting states, which is connected to a topological nodal-to-nodeless transition in altermagnets with magnetic field, making our results applicable to a wide range of altermagnets.

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Debmalya Chakraborty, Annica M. Black-Schaffer. 2024-08-14. Perfect superconducting diode effect in altermagnets. https://arxiv.org/abs/2408.07747

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