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arXiv · 2401.16935

Superconducting spin valves based on antiferromagnet/superconductor/antiferromagnet heterostructures

G. A. Bobkov·V. M. Gordeeva·Lina Johnsen Kamra·Simran Chourasia·A. M. Bobkov·Akashdeep Kamra·I. V. Bobkova
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Abstract

Proximity effect at superconductor/antiferromagnet (S/AF) interfaces, which manifests itself as generation of Neel-type triplet correlations, leads to sensitivity of the superconducting critical temperature to the mutual orientation of the AF Neel vectors in AF/S/AF trilayers, which is called the spin-valve effect. Here we predict that the spin-valve effect in AF/S/AF heterostructures crucially depends on the value of the chemical potential of the superconducting interlayer due to the occurrence of the finite-momentum Neel triplet correlations. In addition we investigate equal-spin triplet correlations, which appear in AF/S/AF structures for non-aligned Neel vectors of the AFs, and their role in the nonmonotonic dependence of the superconducting critical temperature of the AF/S/AF structure on the mutual orientation of the AF Neel vectors. The influence of impurities on the spin-valve effect is also investigated.

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G. A. Bobkov, V. M. Gordeeva, Lina Johnsen Kamra, Simran Chourasia, A. M. Bobkov, Akashdeep Kamra, I. V. Bobkova. 2024-01-30. Superconducting spin valves based on antiferromagnet/superconductor/antiferromagnet heterostructures. https://doi.org/10.1103/physrevb.109.184504

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