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The nonlinear absorption of a short laser on metal surfaces, embedded with metallic nanoparticles and nanotubes, is studied theoretically. The absorption is resonantly enhanced by the surface plasmon resonance where the laser frequency becomes comparable to the frequency of surface charge oscillations. Heat conduction inside the metal limits the rise in electron temperature. The absorption coefficient increases with the angle of incidence for all frequencies. For expanding clusters, the heating rate rises with time, attaining a sharp maximum at the instant when the plasmon resonance occurs. Beyond this time, the electron temperature falls due to thermal conduction. Similar effects are observed in the case of carbon nanotubes. [ABSTRACT FROM AUTHOR]

An analytical formalism is developed to study the nonlinear propagation of a high power laser through an array of parallel carbon nanotubes and generation of second and third harmonics. The array is mounted on a planar surface, and a laser propagates perpendicular to the lengths of the tubes. The nonlinearity arises through the electrostatic restoration force on the displaced electron cylinder with respect to the ion cylinder by the laser. The effect is resonantly enhanced near the surface plasmon resonance. For typical powers of the laser and areal density of nanotubes of radius 2 × 10−8 m, the attenuation length turns out to be 5 cm. The second harmonic conversion efficiency is of the order of 1.4 × 10−2, while the third harmonic conversion efficiency is 0.9 × 10−2. [ABSTRACT FROM AUTHOR]