Аннотация:
We present experimental investigations of ultrafast phase transitions in tellurium following excitation with an intense femtosecond laser pulse. Femtosecond time-resolved polarization-sensitive microscopy is used to monitor the temporal evolution of the optical anisotropy (birefringence) of the irradiated material. The decay of the optical anisotropy associated with the loss of order in crystalline tellurium is fluence dependent and occurs within 0.5-3 ps.