论文标题
PT/FERH界面处的飞秒光电流
Femtosecond Photocurrents at the Pt/FeRh Interface
论文作者
论文摘要
FERH/PT双层的飞秒激光激发在PT层中发射了电动光电流的超快脉冲，因此导致电磁辐射在THZ光谱范围内排放。分析THZ发射是飞秒激光脉冲，外部磁场，样品温度和样品取向的偏振的函数，表明光电流可以由于Ferh/Pt界面处的垂直自旋泵和垂直诱导的逆旋转轨道扭矩而出现。从FERH到PT的垂直自旋泵送不取决于光的极化，而是来自Ferh的铁磁相的超快激光诱导的磁磁化。在FERH/PT界面处的光诱导的逆自旋轨道扭矩可以用圆形极化光对铁磁FERH的磁化以及随后产生光电流的磁化的影响来描述。
Femtosecond laser excitation of FeRh/Pt bilayers launches an ultrafast pulse of electric photocurrent in the Pt-layer and thus results in emission of electromagnetic radiation in the THz spectral range. Analysis of the THz emission as a function of polarization of the femtosecond laser pulse, external magnetic field, sample temperature and sample orientation shows that photocurrent can emerge due to vertical spin pumping and photo-induced inverse spin-orbit torque at the FeRh/Pt interface. The vertical spin pumping from FeRh to Pt does not depend on the polarization of light and originates from ultrafast laser-induced demagnetization of the ferromagnetic phase of FeRh. The photo-induced inverse spin-orbit torque at the FeRh/Pt interface can be described in terms of a helicity-dependent effect of circularly polarized light on the magnetization of the ferromagnetic FeRh and subsequent generation of a photocurrent.
