ANOMALOUS 2ND-HARMONIC GENERATION IN BATIO3 THIN-FILMS

We present data on second harmonic generation in as-grown BaTiO3 thin films, including the dependence of the second harmonic intensity on th e incidence angle and on the polarization direction of the fundamental beam. The data indicate that the effective second harmonic generation coefficient in these films is unrelated to the crystallographic orien tation of the BaTiO3 as determined by x-ray diffraction. We suggest as an alternative explanation electric-field-induced second harmonic gen eration. (C) 1996 American Institute of Physics.