Preliminary photoemission studies of the van der Waals material Fe₂Ga₂S₅

Angle-resolved photoemission spectroscopy is a powerful tool for probing the band structure and orbital character of two-dimensional van der Waals materials. Research has 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. We use ARPES to reveal the band structure of Fe₂Ga₂S₅ and the symmetry of the Fermi surface, which we contrast with our collaborator’s theoretical calculations. We acquired photoemission data at various polarizations to analyze both linear and circular dichroism in search of insight about the Fe₂Ga₂S₅'s orbital orientations and the proper band identification to contrast with our density functional theory calculations. Temperature series were also conducted around the Néel Temperature of Fe₂Ga₂S₅ to investigate the change of the band structure in the paramagnetic and antiferromagnetic regimes. We try to consolidate our photoemission results with the electronic transport experiments of our collaborators, that find that thin crystals of this material behave as a heavily p-doped semiconductor.