Reversal of magnetization of a single-domain magnetic particle by the ac field of time-dependent frequency

Article

关键词: BROAD-BAND;    DYNAMICS;    INVERSION;    PASSAGE;   

DOI  :  10.1103/PhysRevB.87.024418

来源: SCIE

【 摘 要 】

We report numerical and analytical studies of the reversal of the magnetic moment of a single-domain magnetic particle by a circularly polarized ac field of time-dependent frequency. For the time-linear frequency sweep, the phase diagrams are computed that illustrate the dependence of the reversal on the frequency sweep rate nu, the amplitude of the ac field h, the magnetic anisotropy field d, and the damping parameter alpha. It is shown that the most efficient magnetization reversal requires a nonlinear time dependence of the frequency, omega(t), for which an exact analytical formula is derived with account of damping. The necessary condition of the reversal is h > alpha d. Implementation of a small-scalemagnetization reversal is proposed in which a nanomagnet is electromagnetically coupled to two weak superconducting links controlled by the voltage. The dynamics of such a system is analyzed with account of the back effect of the magnet on the superconducting links. DOI: 10.1103/PhysRevB.87.024418

【 授权许可】

Free