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A high power laser of frequency ω incident on a rippled metal surface gives rise to oscillatory electron velocity v2ω at the second harmonic in the skin layer. Its coupling with the surface ripple (modeled as a density ripple) of suitable wave number produces a nonlinear current, driving a surface plasma wave at frequency 2ω. [ABSTRACT FROM AUTHOR]

A surface-plasmon sensor, in the attenuated-total-reflection configuration, is modeled by a glass-metal-dielectric-air structure, where a dielectric film with anisotropic permittivity models the material (or particulates) to be sensed. The laser beam, polarized in the plane of incidence, is obliquely incident on the glass-metal interface from the glass side. At a particular angle of incidence θr, the laser beam excites a surface plasma wave at the metal-dielectric interface, and the reflectivity is at a minimum. The minimum reflectivity angle θr increases linearly with the thickness of the dielectric film and is sensitive to the components of the permittivity tensor. The depth and half-width of the reflectivity minimum, however, remain practically unchanged. [ABSTRACT FROM AUTHOR]

A large-amplitude surface plasma wave (SPW) over a metal-vacuum interface Ohmically heats the electrons and undergoes nonlinear absorption. The attenuation rate increases with the local SPW amplitude. The enhanced electron temperature leads to stronger thermionic emission of electrons. At typical Nd:glass laser intensity IL=7 GW/cm2, if one takes the amplitude of the SPW to be ≈6 times the amplitude of the laser, one obtains the thermionic electron emission current density J=200 A/cm2. However, the emission current density decreases with propagation distance at a much faster rate than the SPW amplitude and electron temperature. [ABSTRACT FROM AUTHOR]