Time- and angle-resolved photoemission spectroscopy of the intrinsic antiferromagnetic topological insulator EuSn₂P₂

EuSn₂P₂ was recently predicted to be an antiferromagnetic topological insulator below T_N = 30 K. This makes it an ideal candidate to explore the interplay between magnetism and topology including axion electrodynamics. Here we use time- and angle- resolved photoemission spectroscopy (tr-ARPES) to observe and characterize the Dirac surface states of EuSn₂P₂ both above and below T_N. An IR pump pulse populates the previously unoccupied surface states near the Dirac point and a time delayed probe pulse measures the transient ARPES spectra. We will discuss changes in the tr-ARPES decay dynamics across the magnetic transition and further understand the topological nature of the bands using circular dichroism ARPES.