电子能量损失谱磁手性二向色性研究进展

电子能量损失谱磁手性二向色性技术是近年发展起来的实验方法,它与X射线磁圆二向色性一样可以测量特定元素的自旋与轨道磁矩的信息,由于其高空间分辨率、实验方法多样和对设备要求简单,因此有望应用于对微观材料的磁性测量和研究。本文简要介绍了该方法的背景、理论基础、实验方法、研究进展和应用。

Investigation process of electron magnetic chiral dichroism

Electron magnetic chiral dichroism（EMCD）,as a recent years developed technique similar to X-ray magnetic circular dichroism（XMCD）,was first predicted in 2003 and achieved in 2006.It can directly determine the spin and orbital magnetic moments of the selected elements using sum rules in transmission electron microscope（TEM） as the magnetic materials have different electron energy loss spectrums（EELS） in the two inverse chiral positions of the diffraction space.The EMCD technique has ultra high special resolution（toward atomic resolution）,variable experimental methods（normal diffraction mode,large angle convergent diffraction（LACDIF）mode,convergent beam electron diffraction（CBED） mode and energy spectroscopic diffraction or image（ESD or ESI） mode） and lesser requirement of equipment（a transmission electron microscope equipped with energy filtered system） compared with XMCD,thus EMCD can be hopefully applied to the measurement and research of the microscopic materials’ magnetic properties.This paper briefly describes the background,theory,experimental methods,progress,and applications of the EMCD technique.