NbN-Based Ferromagnetic 0 and π Josephson Junctions

In superconducting spintronics, ferromagnetic π Josephson junctions are attractive for qubits, cryogenic memory, and phase shifters in logic circuits, offering reduced cell size and superior coherence and scalability. This study demonstrates such junctions based on niobium nitride, which can be grown epitaxially on MgO and is compatible with existing hardware. Its results provide physical insight into superconducting spintronics, as well as an interesting component for applications in quantum information processing.