Influence of electron doping on the ground state of (Sr1-xLax)2IrO4

The evolution of the electronic properties of electron-doped (Sr1-xLax)2IrO4 is experimentally explored as the doping limit of La is approached. As electrons are introduced, the electronic ground-state transitions from a spin-orbit Mott phase into an electronically phase separated state, where long-range magnetic order vanishes beyond x=0.02 and charge transport remains percolative up to the limit of La substitution (x≈0.06). In particular, the electronic ground state remains inhomogeneous even beyond the collapse of the parent state's long-range antiferromagnetic order, while persistent short-range magnetism survives up to the highest La-substitution levels. Furthermore, as electrons are doped into Sr2IrO4, we observe the appearance of a low-temperature magnetic glasslike state intermediate to the complete suppression of antiferromagnetic order. Universalities and differences in the electron-doped phase diagrams of single-layer and bilayer Ruddlesden-Popper strontium iridates are discussed.