Single domain spectroscopic signatures of a magnetic Kagome metal

Spin- and orbital-resolved access to the electronic bands is necessary to establish key properties of quantum materials such as the quantum-geometric tensor. Despite recent revival on magnetic Kagome compounds, no spectroscopic access to their magnetic properties has been available so far due to small domain sizes and lack of appropriate techniques. Furthermore, their real space magnetic texture is often complex and temperature-dependent. We investigate the magnetic Kagome metal DyMn$_6$Sn$_6$ using high-resolution micro-focused circular-dichroic angle-resolved photoemission ($μ$-CD-ARPES) to probe its magnetic and electronic properties. By tuning the kinetic energy to various features of the Dy $4f$ multiplet, we resolve magnetic domains in samples cryo-cooled down to 20 K. Smaller, but clear signatures are detected in the Mn $3p$ levels. The behavior of both Dy $4f$ and Mn $3p$ features are in remarkable agreement with our modeling based on the Hartree-Fock method, revealing ferrimagnetic alignment of Dy and Mn local moments, and further strengthening our interpretation. Adjusting the energy to the Mn $3d$-dominated valence bands reveals signatures which we relate to the orbital magnetization through a comparison to {\it ab initio} electronic structure calculations. Our study establishes the spectroscopic access to a single magnetic domain in a Kagome metal, paving the way for further research into imaging magnetic phases of novel magnetic materials using $μ$-CD-ARPES.