Complete $T_c$ suppression and N\'eel triplets-mediated exchange in antiferromagnet-superconductor-antiferromagnet trilayers

TL;DR

This paper theoretically demonstrates how Ne9el triplet Cooper pairs in antiferromagnet-superconductor-antiferromagnet trilayers enable control of the superconducting critical temperature and mediate exchange interactions between antiferromagnetic layers.

Contribution

It introduces a novel mechanism where Ne9el triplets control Tc and mediate exchange in AFI-S-AFI trilayers, with signatures depending on the number of superconductor monolayers.

Findings

Tc can be controlled via the angle between Ne9el vectors.

The sign of the angle dependence changes with the number of S monolayers.

Ne9el triplets mediate a distinct exchange interaction.

Abstract

An antiferromagnetic insulator (AFI) bearing a compensated interface to an adjacent conventional superconductor (S) has recently been predicted to generate N\'eel triplet Cooper pairs, whose amplitude alternates sign in space. Here, we theoretically demonstrate that such N\'eel triplets enable control of the superconducting critical temperature in an S layer via the angle between the N\'eel vectors of two enclosing AFI layers. This angle dependence changes sign with the number of S monolayers providing a distinct signature of the N\'eel triplets. Furthermore, we show that the latter mediate a similarly distinct exchange interaction between the two AFIs' N\'eel vectors.