Magnetic control of superconducting heterostructures using compensated antiferromagnets

TL;DR

This paper demonstrates that compensated antiferromagnetic layers can influence superconducting phase transitions by proximity coupling, enabling control via magnetization rotation and affecting triplet Cooper pair spin states.

Contribution

It reveals that compensated antiferromagnets can control superconductivity and distinguish triplet pair spin-polarizations, contrary to previous assumptions.

Findings

Superconducting critical temperature can be modulated by in-plane magnetization rotation.

Antiferromagnetic interfaces can distinguish between different triplet Cooper pair spin states.

Superconducting phase transition can induce reorientation of magnetization.

Abstract

Due to the lack of a net magnetization both at the interface and in the bulk, antiferromagnets with compensated interfaces may appear incapable of influencing the phase transition in an adjacent superconductor via the spin degree of freedom. We here demonstrate that such an assertion is incorrect by showing that proximity-coupling a compensated antiferromagnetic layer to a superconductor-ferromagnet heterostructure introduces the possibility of controlling the superconducting phase transition. The superconducting critical temperature can in fact be modulated by rotating the magnetization of the single ferromagnetic layer within the plane of the interface, although the system is invariant under rotations of the magnetization in the absence of the antiferromagnetic layer. Moreover, we predict that the superconducting phase transition can trigger a reorientation of the ground state magnetization. Our results show that a compensated antiferromagnetic interface is in fact able to distinguish between different spin-polarizations of triplet Cooper pairs.