Laser-induced ultrafast phase transitions in solids using optical anisotropy

A new method of crystalline order detection in highly absorbing anisotropic crystals is worked out. The method is based on partial transformation of incident p-polarized electromagnetic wave into s-polarized reflected wave due to optical anisotropy. The method makes possible to follow changes of crystalline structure in thin (10-6 - 10-5 cm) surface layers of solids. Using picosecond laser pulses and streak camera 'Agat,' surface melting and evaporation of Zn and C (graphite) are studied. Direct observation of the melting of graphite subjected to picosecond laser pulse is performed. The kinetics of solidification of fused surface layers are studied.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.