Spin-Transfer Torque Switching in Nanopillar Superconducting-Magnetic Hybrid Josephson Junctions

Although both superconducting and magnetic devices have the potential to overcome limitations of current CMOS technology, traditionally they have remained separate areas of research. Here the authors develop nanopillar Josephson junctions with pseudo-spin-valve barriers that provide a unique, hybrid superconducting-magnetic capability. The states of these devices are written using spin-transfer torque and read using Josephson coupling, and yield 10-fold changes in superconducting critical current. This approach holds the promise for nanoscale, nonvolatile, cryogenic memory in future ultralow-power computing systems.