Relaxation Dynamics at High-symmetry Points in Sr₂IrO₄ through Time- and Angle-resolved Photoemission Spectroscopy

The unresolved mechanism that underlies high-T_c superconductivity in cuprates has stimulated the search for new material platforms that could shed light on this long-standing puzzle. A promising candidate is electron-doped Sr₂IrO₄ – an antiferromagnetic Mott insulator with strong spin-orbit coupling. Pioneering studies have shown that chemical doping modifies the electronic band structure in electron-doped Sr₂IrO₄. However, instead of chemical doping, which provides a static modification of the electronic band structure, transient photo-doping with an ultrafast laser pulse can be considered. Through time- and angle-resolved photoemission spectroscopy, we performed momentum-resolved pump-probe experiments and compared the electron relaxation behavior at high-symmetry points (Γ, M, and X) of the Brillouin zone. This time- and momentum-resolved study provides new insights into the transient charge dynamics in this Mott insulator.