  We determine the motion of a charge (hole or electron) added to the Mott
insulating, antiferromagnetic (AF) ground-state of quasi-2D iridates such as Ba
2 IrO 4 or Sr 2 IrO 4 . We show that correlation effects, calculated within the
self-consistent Born approximation, render the hole and electron case very
different. An added electron forms a spin-polaron, which closely resembles the
well-known cuprates, but the situation of a removed electron is far more
complex. Many-body 5d 4 configurations form which can be singlet and triplets
of total angular momentum J and strongly affect the hole motion between AF
sublattices. This not only has important ramifications for the interpretation
of (inverse-)photoemission experiments of quasi-2D iridates but also
demonstrates that the correlation physics in electron- and hole-doped iridates
is fundamentally different.
