DFG Project Vortex-EMCD

Atomically resolved EMCD on ferrimagnets measured with electron vortex beams

Funding Period: 2022-2025

Electron vortex beams (EVBs) carry a discrete orbital angular momentum (OAM), L, and are predicted to reveal electron energy loss magnetic chiral dichroism (EMCD) upon interacting with magnetic samples down to the atomic scale. However, proof-of-concept experiments so far failed since the weak magnetic signal is still hidden behind the poor signal-to-noise ratio (SNR) of the acquired spectra. Within this project we therefore seek to develop strategies to improve the SNR on the methodical side as well as on the materials side – both of which are essential for a successful proof-of-concept experiment. We anticipate to build a fundamental understanding of how electron vortex beams with high spatial coherence and purity can be generated and how different material properties impact on the SNR for the detection of an atomically resolved EMCD signal.