Based on the Landau-Lifshitz-Gilbert equation, it can be shown that a circularly polarized microwave can reverse the magnetization of a Stoner particle through synchronization. In comparison with magnetization reversal induced by a static magnetic field, it can be shown that when a proper microwave frequency is used the minimal switching field is much smaller than that of precessional magnetization reversal. A microwave needs only to overcome the energy dissipation of a Stoner particle in order to reverse magnetization, unlike the conventional method with a static magnetic field where the switching field must be of the order of magnetic anisotropy.

• Received 23 August 2006

DOI:https://doi.org/10.1103/PhysRevB.74.132401