PHOTOELECTRIC EFFECT FROM A METAL-SURFACE - A REVISITED THEORETICAL-MODEL

The Sommerfeld model extended to include radiation-electron interaction in the regime of highly intense fields is taken as the basis for studying theoretically the laser multiphoton photoelectric effect from a metal surface. Numerical analysis is carried out without approximations other than those inherent in the model itself; the study of the multiphoton aspect of the problem is based on a scheme that is nonperturbative in an essential way. The numerical analysis facilitates insight into the potential and the limits of the model in the interpretation of recent experiments and into the similarities and differences between the metal multiphoton effect and atomic multiphoton ionization. The results obtained and the importance of the competing processes not considered here clearly call for more realistic models to account for recent laboratory observations.