  Strontium ruthenates have many similarities with copper oxide superconductors
and are of particular interest for the investigation of the mechanisms and
conditions which lead to high-temperature superconductivity. We report here on
multiple experimental indications of superconductivity with onset at 40 K in
strontium ruthenate doped by rhenium and selenium with chlorine used as the
flux. The main experimental evidence arises from terahertz spectroscopy of this
material followed by AC and DC magnetization, as well as measurements of its
heat capacity and magnetoresistance. Structural and morphological studies
revealed the heterophase nature of this polycrystalline material as well as the
changes of lattice parameters relative to the original phases. Experimental
data show a higher critical temperature on the surface compared to that of the
bulk of the sample.
