All electrical sub-nanosecond field-free switching of perpendicular magnetization with high magnetic field immunity

Spin-orbit torque magnetic random-access memory is a promising next-generation non-volatile memory technology featuring low power consumption, rapid operation, and high endurance. Conventional spin-orbit torque-induced deterministic perpendicular magnetization switching, however, typically requires the assistance of an external magnetic field. While multiple field-free switching strategies have been demonstrated, most suffer from significant limitations. Here, we present a straightforward and reliable approach for field-free switching of perpendicular magnetization utilizing two orthogonal electrical currents. The method employs only conventional heavy metals as spin current sources and enables seamless integration into existing manufacturing lines as it is fully compatible with standard fabrication processes for commercialized spin-transfer torque magnetic random-access memory. Notably, the approach also achieves ultrafast magnetization switching with robust immunity against external magnetic fields along all directions.