Magnetic Circular Spectroscopy in TEM: Investigation of Magnetic Property-Structure Relationship at the atomic scale

New energy-efficient information and communications technologies place ever-increasing demands on the improved performance of magnetic materials. The development of new materials to meet these challenges requires atomic-level characterization of the constituent magnetic moments, in order to predict and control their physical properties and to obtain a fundamental understanding of the interplay between charge, spin, orbital and lattice degrees of freedom. One of the most powerful techniques for imaging magnetic microstructure in the TEM is electron energy-loss magnetic chiral dichroism (EMCD) [1]. The technique is similar to XMCD, in that it permits quantitative element-selective determination of spin and orbital magnetic moments in crystalline materials from spectra measured at core loss edges [2]. When compared to XMCD, EMCD offers higher spatial resolution and greater depth sensitivity due to the short de Broglie wavelength and penetration of high-energy electrons [3]. Here we would like to introduce our recent works on the high spatial resolution EMCD.