Micro-optical nonlinearity of a silver oxide layer

We studied the near-field formation mechanism of a silver oxide thin film sandwiched between protective layers using a pump probe with nanosecond laser pulse irradiation and tapping-mode tuning-fork near-field scanning optical microscopy. A multilayer composed of ZnS-SiO2/Ag2O/ZnS-SiO2 showed abnormal optical nonlinear properties compared to ordinary third-order nonlinear materials. The Ag2O layer played a role in generating a strong light scattering center in a reversible chemical reaction in only a small area of the multilayer, and the optical near field produced about the scattering center was 40 times stronger than that produced by an antimony layer instead of Ag2O. (C) 2001 American Institute of Physics.