Effect of laser wavelength and pulse duration on laser-light absorption and back reflection

Absorption efficiency has been measured in laser-irradiated plane targets experiments with various laser wavelengths (1.06, 0.53, and 0.26 ..mu..m), pulse durations (100 ps, 2 ns), and intensities (10/sup 10/--(2 x 10/sup 15/) W/cm). Results show a strong increase of absorption for long pulses, low intensities, and short wavelengths which favor inverse bremsstrahlung absorption. A one-dimensional Lagrangian hydrocode (fIlm) is used to interpret these results.