Superconducting Diode Effect in a Constricted Nanowire

Abstract

Due to isotropic superconducting properties and the lack of breaking of inversion symmetry for conventional s-wave superconductors, a nonreciprocal superconducting diode effect is absent. Recently, a series of superconducting structures, including superconducting superlattice, and quantum-material-based superconducting Josephson junction, have exhibited a superconducting diode effect in terms of polarity-dependent critical current. However, due to complex structures, these composite systems are not able to construct large-scale integrated superconducting circuits. Here, it is demonstrated that the minimal superconducting electric component-superconducting nanowire-based diode with a nonreciprocal transport effect under a perpendicular magnetic field, in which the superconducting to normal metallic phase transition relies on the polarity and amplitude of the bias current. These nanowire diodes can be reliably operated near at all temperatures below the critical temperature, and the rectification efficiency at 2 K can be more than 24%. Moreover, the superconducting nanowire diode is able to rectify both square wave and sine wave signals. Combining the superconducting nanowire-based diodes and transistors, superconducting nanowires hold the possibility to construct novel low-dissipation superconducting integrated circuits.