  Superconducting electrodes are an integral part of hybrid Josephson junctions
used in many applications including quantum technologies. We report on the
fabrication and characterization of superconducting hybrid Au/YBa2Cu3O7-x
(YBCO) electrodes on vicinal substrates. In these structures, superconducting
CuO2-planes face the gold film, resulting in a higher value and smaller
variation of the induced energy gap compared to the conventional Au/YBCO
electrodes based on films with the c-axis normal to the substrate surface.
Using scanning tunneling microscopy, we observe an energy gap of about 10-17
meV at the surface of the 15- nm-thick gold layer deposited in situ atop the
YBCO film. To study the origin of this gap, we fabricate nanoconstrictions from
the Au/YBCO heterostructure and measure their electrical transport
characteristics. The conductance of the nanoconstrictions shows a series of
dips due to multiple Andreev reflections in YBCO and gold providing clear
evidence of the superconducting nature of the gap in gold. We consider the
Au/YBCO electrodes to be a versatile platform for hybrid Josephson devices with
a high operating temperature.
