We propose an experimental approach to extract separately the surface and interface phase shift of standing
waves in metallic quantum well (QW) structures composed of isostructural perovskite oxides. The “asymmetric”
vacuum/SrVO3/SrTiO3 and “symmetric” SrTiO3/SrVO3/SrTiO3 QW structures are fabricated in an epitaxial
multilayer form. Using these metallicQWstructures, the phase shifts at the surface (vacuum/SrVO3) and interface
(SrTiO3/SrVO3) are successfully obtained by analyzing a thickness series of angle-resolved photoemission
spectra. The difference of the phase shift between the two boundaries reveals that nearly ideal quantum
confinement is achieved at the interface, indicating that a SrTiO3 layer acts as a useful potential barrier.