Oscillation of the optical second-harmonic generation intensity during Ag thin film growth on a Si(111)7X7 surface - art. no. 195415

The optical second harmonic generation (SHG) intensity demonstrated clear o scillations during Ag thin film growth on an Si(111)7x7 surface at room tem perature. The first intensity peak appeared at two monolayer (ML) for 1.20, 1.30, and 1.40 eV pump photon energies, and the second peak shifted to a l ower coverage side with increases in the excitation photon energy. The SHG spectra and atomic force microscope images indicated that the first peak wa s due to local field enhancement by the plasmon confined in isolated Ag isl ands. The second peak was caused by resonance with the quantized electronic states confined in the flat Ag thin film.