Projekttitel: Atomic resolution electron magnetic circular dichroism by aberration-corrected transmission electron microscopy
Huvudsökande Uppsala universitet: Ján Rusz, avdelningen för materialteori
Huvudsökande Tsinghua University: Xiaoyan Zhong
Beviljade medel: 390 000 SEK för perioden 2020-2023
An atomic-level knowledge of local spin configuration of magnetic materials is of great importance to predict and control their physical properties, in order to meet the challenges of ever-increasing demands on performance of functional materials. In this joint proposal, we would like to develop a method to access the electron magnetic circular dichroism (EMCD) atomic plane by atomic plane by two different approaches and provide direct insight into magnetic spins in materials at the atomic scale. One is using atomic-sized electron probe with controlled beam displacement in a aberration-corrected scanning transmission electron microscope (AC-STEM), the other is using spatially resolved electron energy loss spectroscopy (SR-EELS) in a chromatic/spherical aberration corrected transmission electron microscope (TEM). We will combine the expertise of the Tsinghua partner in the measurement of atomic-scale EMCD in parallel beam illumination mode, with the expertise of the Uppsala partner in dynamical diffraction simulation of EMCD signals and in measurement of EMCD using an atomic-sized electron probe in convergent beam illumination mode. These information will not only contribute to a fundamental understanding of the local interplay between charge, spin, orbital and lattice degrees of freedom in magnetic functional materials, but also pave the way for new of magnetic materials.
