Frontiers in all electrical control of magnetization by spin orbit torque.

Achieving all electrical control of magnetism without assistance of an external magnetic field has been highly pursued for spintronic applications. In recent years, the manipulation of magnetic states through spin-orbit torque (SOT) has emerged as a promising avenue for realizing energy-efficient spintronic memory and logic devices. Here, we provide a review of the rapidly evolving research frontiers in all electrical control of magnetization by SOT. The first part introduces the SOT mechanisms and SOT devices with different configurations. In the second part, the developments in all electrical SOT control of magnetization enabled by spin current engineering are introduced, which include the approaches of lateral symmetry breaking, crystalline structure engineering of spin source material, antiferromagnetic order and interface-generated spin current. The third part introduces all electrical SOT switching enabled by magnetization engineering of the ferromagnet, such as the interface/interlayer exchange coupling and tuning of anisotropy or magnetization. At last, we provide a summary and future perspectives for all electrical control of magnetization by SOT.