We have determined the structure of the interface between an epitaxial crystalline oxide and silicon, including the sub-Å distortions of the silicon and oxide caused by the strain of connecting the two crystal lattices at the interface.
To achieve this result, we combined several techniques:
- Precise MBE growth of BaO
- Synchrotron X-ray diffraction
- X-rays shine from the left
- Scatter from the interface
- Form on image on a CCD
- First principles theory
- Model interface structure
We find that an extra atomic layer of oxygen is incorporated at the interface, changing the band offset.