Xray Absorption FineStructure Determination of Interfacial Polarization in SrT1ptiO3 Thin Films Grown on Si001

Polarization-dependent x-ray absorption fine structure together with x-ray diffraction have been used to study the local structure in SrTiO3 thin films grown on Si(001). Our data indicate that an interfacial polarization of the SrTiO3 layer by the Si substrate results in a tetragonal distortion of the SrTiO3 unit cell.