Fig. 1. Thermodynamics background.

(A) Description of single-bit reset by time sequence. Before the erasure, the memory stores information in state 0 or 1; after the reset, the memory stores information in state 0 in accordance with the unit probability. (B) Timing diagram for the external magnetic fields applied during the restore-to-one process. H_x is applied along the magnetic hard axis to remove the uniaxial anisotropy barrier, whereas H_y is applied along the easy axis to force the magnetization into the 1 state. Illustrations are provided of the magnetization of the nanomagnet at the beginning and end of each stage and of the direction of the applied field in the x-y plane.