Preliminary Photoemission studies of the van der Waals material Fe₂Ga₂S₅

Angle-resolved photoemission spectroscopy (ARPES) is a powerful tool for probing the band structure and its orbital character in two-dimensional van der Waals materials. Previous works have shown that Fe₂Ga₂S₅ is an antiferromagnetic semiconducting material with a narrow band gap of 5 meV and a Neel temperature of 110 K. The electronic structure of this material has not been studied in depth yet. Interestingly, it has a crystalline structure that is very similar to the one of Mn₂Ga₂S₅, known to be a spin glass.

Here, we use ARPES to reveal the band structure of Fe₂Ga₂S₅ and the symmetry of its Fermi surface, which we contrast with first-principles calculations. We acquired photoemission data at various light polarizations to analyze the linear and circular dichroism in search of insight about the orbital character of the Fe₂Ga₂S₅’s electronic states and the proper band identification to contrast with our density functional theory (DFT) calculations. Temperature series were also conducted around the Néel Temperature (T_N) of Fe₂Ga₂S₅ to investigate the change of the band structure in the paramagnetic and antiferromagnetic regimes.