Spin-transfer torque switching in nanopillar superconducting-magnetic   hybrid Josephson junctions
  The combination of superconducting and magnetic materials to create novel superconducting devices has been motivated by the discovery of Josephson critical current (Ics) oscillations as a function of magnetic layer thickness and the demonstration of devices with switchable critical currents. However, none of the hybrid devices have shown any spintronic effects, such as spin-transfer torque, which are currently used in room-temperature magnetic devices, including spin-transfer torque random-access memory and spin-torque nano-oscillators. We have developed nanopillar Josephson junctions with a minimum feature size of 50 nm and magnetic barriers exhibiting magnetic pseudo-spin-valve behavior at 4 K. These devices allow current-induced magnetization switching that results in 20-fold changes in Ics. The current-induced magnetic switching is consistent with spin-transfer torque models for room-temperature magnetic devices. Our work demonstrates that devices that combine superconducting and spintronic functions show promise for the development of a nanoscale, nonvolatile, cryogenic memory technology. 
Burm Baek, William H. Rippard, Matthew R. Pufall, Samuel P. Benz,   Stephen E. Russek, Horst Rogalla, and Paul D. Dresselhaus
cond-mat.supr-con