2ND-HARMONIC GENERATION AND PHOTOEMISSION FROM SILVER

We have observed photoemission induced by second-harmonic photons from a NH3-covered Ag film in the attenuated-total-reflection configuration. The photoyield increases as the square of the laser intensity. The dispersion relation for the photoemission is identical with that for the surface-plasmon-polariton. The angular variations of the reflectance and of the photoyield are accurately described by standard Fresnel optics when dielectric constants close to those found in the literature and a reasonable value of the electron escape length are used. Photons from a pulsed dye laser with energies in the range 1.8-2.6 eV were used. Measurements of the reflectance and photoyield were made simultaneously.