SURFACE-PLASMON ENHANCED SHG FROM A HEMICYANINE MONOLAYER

Surface plasmon enhancement of second-harmonic generation has been investigated in a Langmuir-Blodgett monolayer of a hemicyanine dye deposited on a silver substrate. Measurements are reported for different thicknesses of silver. The signals obtained were 10**3 times larger than the corresponding results without enhancement. The second-harmonic signal from the dye monolayer, which is 50 times larger than that from silver alone, is analyzed in terms of an effective surface second-order susceptibility. This is compared with previous estimates. The results are discussed with reference to film uniformity and to the general aspects of guided mode second-harmonic generation.