  The large spin-orbit coupling in iridium oxides plays a significant role in
driving novel physical behaviors, including emergent phenomena in the films and
heterostructures of perovskite and Ruddlesden-Popper iridates. In this work, we
study the role of epitaxial strain on the electronic behavior of thin SrIrO$_3$
films. We find that compressive epitaxial strain leads to metallic transport
behavior, but a slight tensile strain shows gapped behavior.
Temperature-dependent resistivity measurements are used to examine different
behaviors in films as a function of strain. We find Kondo contributions to the
resistivity, with stronger effects in films that are thinner and under less
compressive epitaxial strain. These results show the potential to tune
SrIrO$_3$ into Kondo insulating states and open possibilities for a quantum
critical point that can be controlled with strain in epitaxial films.
