Dynamics of Ultrafast Phase Changes in Amorphous GeSb Films

Abstract

Time resolved imaging has been used to analyze structural transformations induced by intense 100 fs laser pulses in amorphous GeSb films. Above a threshold of 19 mJ/ ${\mathrm{cm}}^{2}$ the data show the formation of a transient nonequilibrium state of the excited material within 300 fs. The results are consistent with an electronically induced, amorphous-to-crystalline phase transition.