In situ ARPES on Sr2IrO4 thin films electron and hole-doped via cation substitution

Sr$_2$IrO$_4$, a Mott insulator with spin-orbit coupling, has garnered much attention due to its similarities to the prototypical cuprate superconductor La$_2$CuO$_4$ and its predicted high temperature superconductivity. It is thus essential to explore the full phase diagram of Sr2IrO4. We grow carrier doped Sr$_2$IrO$_4$ epitaxial thin films by oxide molecular beam epitaxy, and characterize the films using in situ angle-resolved photoemission. We present methods for both electron and hole-doping Sr$_2$IrO$_4$ using substitutional doping on the Sr site, thus maintaining the structure of the IrO2 planes, and minimizing the strong disorder scattering which occurs when substituting on the Ir site. We describe the subsequent evolution of the electronic structure by ARPES and transport.