Magnetic-field-free nonreciprocal transport in graphene multiterminal Josephson junctions
Fan Zhang, Asmaul Smitha Rashid, Mostafa Tanhayi Ahari, George J. de Coster, Takashi Taniguchi, Kenji Watanabe, Matthew J. Gilbert, Nitin Samarth, Morteza Kayyalha
Abstract
Nonreciprocal superconducting devices have attracted growing interest in recent years as they potentially enable directional charge transport for applications in superconducting quantum circuits. Specifically, the superconducting diode effect has been explored in two-terminal devices that exhibit superconducting transport in one current direction while showing dissipative transport in the opposite direction. Here, we exploit multiterminal Josephson junctions (MTJJs) to engineer magnetic-field-free nonreciprocity in multiport networks. We show that when treated as a two-port electrical network, a three-terminal Josephson junction (JJ) with an asymmetric graphene region exhibits reconfigurable two-port nonreciprocity. We observe nonreciprocal (reciprocal) transport between superconducting terminals with broken (preserved) spatial mirror symmetry. We explain our observations by considering a circuit network of JJs with different critical currents.