Polarity‐Reversible Zero‐Field Diode Effect in van der Waals Ferromagnetic Josephson Junction for Logic Operation

With unprecedented energy efficiency and quantum‐ready properties, superconducting electronics drive breakthroughs in quantum processors, ultra‐precise sensors, and beyond‐Moore's‐law computing architectures. While nonreciprocal circuit elements such as superconducting diodes are essential for these systems, the realization of practical devices with robust performance remains a major challenge. In particular, polarity‐tunable superconducting diodes that operate efficiently under zero magnetic field are highly desired for practical applications. Here, a polarity‐reversible zero‐field Josephson diode effect (JDE) is demonstrated with highly sustained performance in a vertically stacked 2D van der Waals (vdW) ferromagnetic Josephson junction composed of the Ising superconductor NbSe 2 and the itinerant ferromagnet Fe 3 GeTe 2 (FGT) layers. The diode asymmetry and rectification polarity are primarily tunable via the magnetic state and thickness of the FGT layer. By optimizing the thickness of the FGT layer, a polarity‐reversible JDE is achieved with a rectification efficiency of up to 34.1%. Furthermore, an exclusive OR (XOR) logic gate operation is successfully implemented using this reconfigurable JDE. The work establishes a new route toward realizing efficient, polarity‐reversible, zero‐field superconducting diodes and underscores their potential for 2D non‐dissipative superconducting electronics.