Optical anisotropy as a technique for studying ultrafast phase transformations at solid surfaces

A new technique for testing long-range order in high-absorption anisotropic crystals has been developed using conversion of an incident p-(s-)wave to an s-(p-)wave due to optical anisotropy. The technique yields time-resolved measurements of parameters related to phase transformations in thin (10⁻⁶–10⁻⁵ cm) layers with a high resolution (10⁻¹² s). Using picosecond laser pulses and an “Agat” streak camera, the technique has been applied to an experimental investigation of melting and recrystallization kinetics at zinc and graphite surfaces. It was found that the process of melting takes less than 3 ps and the recrystallization time is about 100 ps. Zh. éksp. Teor. Fiz. 113, 2162–2173 (June 1998)