Enhanced superconducting-vortex diode effect in a superconductor/antiferromagnet heterostructure

Superconducting diodes, characterized by unidirectional flow of supercurrents, are promising components for low-power quantum circuits. In this work, we demonstrate a field-controlled superconducting rectifier in a van der Waals heterostructure comprising an Ising superconductor NbSe 2 and an antiferromagnetic insulator MnPS 3. Our devices display key features of a superconducting-vortex-diode effect, including a characteristic <ani:sans-serif>M</ani:sans-serif>-shaped dependence of the critical current Ic on out-of-plane magnetic fields Bz, and an antisymmetric diode efficiency η with respect to Bz. The second-harmonic magnetotransport measurements confirm that the observed nonreciprocity originates from the strongly asymmetric vortex dynamics, which are significantly enhanced compared to pristine few-layer NbSe 2. We attribute the enhancement to an inversion symmetry breaking induced by the spatially distributed superconducting domains due to the inhomogeneous magnetic proximity effect. Our findings bring insights for developing superconducting-vortex diodes that do not rely on artificial edge or surface disorder to achieve asymmetric barriers for vortex motion.