摘要
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 metallic QW structures, 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.
- 出版日期2013-9-19