Universal route towards field-free electrically polarity-reversible Josephson diode

Abstract

The realisation of superconducting diodes that operate without external magnetic fields and allow electrical control of polarity is a key goal for the integration of nonreciprocal elements into cryogenic and quantum technologies. Here, we demonstrate a universal and scalable approach to achieving such field-free and electrically reconfigurable Josephson diode functionality. Our method relies on long Josephson junctions with ferromagnetic barriers and asymmetric current injection - a configuration that inherently breaks both time-reversal and inversion symmetries. We show that the diode polarity is set by an applied bias current and can be reversed using short current pulses, without the need for magnetic fields or thermal cycling. The effect is robust, material-agnostic, and compatible with standard established fabrication processes. Our results provide a practical platform for integrating low-dissipation, programmable diodes into superconducting and quantum electronic circuits