LASER-SOLID INTERACTION IN THE FEMTOSECOND TIME REGIME

Modification of the surface structure of solid materials by laser radi ation involves a complex chain of processes. The first step is the dep osition of a certain amount of optical energy in the material. The cha racter of the material excitation is strongly dependent on the laser p ulse duration. With the use of ultrashort laser pulses non-equilibrium energy distributions with large excess population in the excited stat es can be produced. The distinct physical processes which come into pl ay in laser-solid interaction on the ultrafast time scale open new rou tes of modifying the structure and the morphology of materials and off er interesting perspectives in laser materials processing.