  In its ground state, RuO2 was long thought to be an ordinary metallic
paramagnet. Recent neutron and x-ray diffraction revealed that bulk RuO2 is an
antiferromagnet (AFM) with TN above 300 K. Furthermore, epitaxial strain
induces novel superconductivity in thin films of RuO2 below 2 K. Here, we
present a resonant elastic x-ray scattering (REXS) study at the Ru L2 edge of
the strained RuO2 films exhibiting the strain-induced superconductivity. We
observe an azimuthal modulation of the 100 Bragg peak consistent with canted
AFM found in bulk. Most notably, in the strained films displaying novel
superconductivity, we observe a ~1 eV shift of the Ru eg orbitals to a higher
energy. The energy shift is smaller in thicker, relaxed films and films with a
different strain direction. Our results provide further evidence of the utility
of epitaxial strain as a tuning parameter in complex oxides.
