Theory of light-induced effective magnetic field in Rashba ferromagnets

Article

关键词: THIN-FILMS;    FARADAY;    REVERSAL;    DYNAMICS;    PULSES;    METALS;    STATE;   

DOI  :  10.1103/PhysRevB.94.014425

来源: SCIE

【 摘 要 】

Motivated by recent experiments on all-optical magnetization reversal in conductive ferromagnetic thin films we use nonequilibrium formalism to calculate the effective magnetic field induced in a Rashba ferromagnet by a short laser pulse. The main contribution to the effect originates in the direct optical transitions between spin-split subbands. The resulting effective magnetic field is inversely proportional to the impurity scattering rate and can reach the amplitude of a few Tesla in the systems like Co/Pt bilayers. We show that the total light-induced effective magnetic field in ferromagnetic systems is the sum of two contributions: a helicity dependent term, which is an even function of magnetization, and a helicity independent term, which is an odd function of magnetization. The primary role of the spin-orbit interaction is to widen the frequency range for direct optical transitions.

【 授权许可】

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