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arXiv · 1904.00233

Superconductivity at metal-antiferromagnetic insulator interfaces

Eirik Løhaugen Fjærbu·Niklas Rohling·Arne Brataas
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Abstract

Magnons in antiferromagnetic insulators couple strongly to conduction electrons in adjacent metals. We show that this interfacial tie can lead to superconductivity in a tri-layer consisting of a metal sandwiched between two antiferromagnetic insulators. The critical temperature is closely related to the magnon gap, which can be in the THz range. We estimate the critical temperature in MnF$_2$-Au-MnF$_2$ to be on the order of 1 K. The Umklapp scattering at metal-antiferromagnet interfaces leads to a d-wave superconductive pairing, in contrast to the p-wave superconductivity mediated by magnons in ferromagnets.

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Eirik Løhaugen Fjærbu, Niklas Rohling, Arne Brataas. 2019-03-30. Superconductivity at metal-antiferromagnetic insulator interfaces. https://doi.org/10.1103/physrevb.100.125432

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