Reconfigurable Physical Unclonable Function Based on Spin-Orbit Torque Induced Chiral Domain Wall Motion
Zhen Zhu Cao, Shuai Zhang, Jian Zhang, Nuo Xu, Ruofan Li, Zhe Guo, Jijun Yun, Min Suk Song, Qiming Zou, Li Xi, OukJae Lee, Xiaofei Yang, Xuecheng Zou, Jeongmin Hong, Long You · IEEE Electron Device Letters · 2021
A reliable design of physical unclonable function (PUF) based on spin-orbit torque (SOT) induced domain wall (DW) motion has been proposed and experimentally demonstrated. Magnetic DWs are nucleated and propagate in Ta/CoFeB/MgO heterostructures in which their device-to-device variation enables the PUF, while cycle-to-cycle variation in DW motion enables the reconfigurable design. Furthermore, field-free SOT switching has been observed in the chiral domain wall likely caused by the large Dzyaloshinskii-Moriya interaction (DMI) effect. The proposed DW motion based anti-counterfeiting device shows good promises as a CMOS-compatible PUF for hardware security.