SPICE Workshop on Hybrid Correlated States and Dynamics in Quantum Materials, May 14th - 16th 2024
Yasen Hou
Accomplishing unequal supercurrents in the forward and backward directions may be expected to enable unprecedented functionalities. This nonreciprocity of critical supercurrents is called superconducting (SC) diode effect. We demonstrate strong SC diode effect in conventional SC thin films, such as niobium and vanadium, employing external magnetic fields as small as 1 Oe. Interfacing the SC layer with a ferromagnetic semiconductor EuS, we further accomplish a non-volatile SC diode effect reaching a giant efficiency of 65%. By careful control experiments and theoretical modeling, we demonstrate that the critical supercurrent nonreciprocity in SC thin films could be easily accomplished with asymmetrical vortex edge/surface barriers and the universal Meissner screening current governing the critical currents. Our engineering of SC diode serves as a building block for novel superconducting devices such as superconducting logics and rectifiers.