Signatures of Magnetic Textures in Josephson Junctions with Altermagnets

Antiferromagnets offers key advantages, such as enhanced robustness against external magnetic fields and the absence of stray fields, enabling more compact device designs. Altermagnets, a recently discovered class of magnetic materials, exhibit many useful properties in addition to their antiferromagnetic properties. In this study, we explore the Josephson effect in a superconductor/altermagnet/superconductor junction, with a focus on the impact of magnetic textures. The symmetry breaking introduced by these textures results in distinct signatures in the current-phase relationship as the junction's axis orientation is adjusted. By breaking both time-reversal and rotational symmetries, we achieve field-free non-reciprocal effects. The unique rotational symmetry of altermagnetic pairing leads to behavior that significantly differs from its ferromagnetic counterpart. Our findings highlight the distinctive nature of textured altermagnetic junctions, distinguishing them from ferromagnetic, antiferromagnetic, and uniform altermagnetic systems.