Mapping out the topological phase diagram of FeSn

Kagome metals exhibit a flat band and a Dirac point in their electronic band structure. The combination of these electronic states with long range magnetic order creates favourable conditions to search for strongly correlated and topological quantum phases of matter. Transition metal based kagome materials have recently emerged as a promising material platform whose electronic and magnetic properties can be controlled by the stoichiometry and elemental composition. Owing to the reduced coupling between the two-dimensional kagome planes, the inter metallic kagome series X₁Y₁ offers particularly attractive opportunities to investigate the interplay between strong electronic correlations, topology, and magnetism.

We have combined molecular beam epitaxy with electrical transport measurements to study the interplay of magnetism and band topology in thin films of the antiferromagnetic kagome metal FeSn. We will present results from a magnetic field and temperature dependent study of the anomalous Hall effect using transverse resistivity measurements. Combining these measurements with magnetic Monte-Carlo simulations and theoretical model calculations, we map out the topological phase diagram of FeSn over a large temperature range.