Phase transition dynamics measurements in superheated liquids by monitoring the ejection of nanometer-thick films

The ejection dynamics of nanometer-thick liquid (isopropanol) films from a substrate caused by a phase transition in a superheated layer at the interface are studied. A nanosecond laser pulse is used to heat the substrate and as a result of heat transfer the fluid adjacent to the surface partially reaches a metastable state. Reflectivity and scattered light measurements demonstrate that the liquid is ejected as an intact layer which redeposits on the time scale of a few hundred nanoseconds. Measurements of the ejection dynamics are shown to be a sensitive method to obtain information about the phase transition, such as the relevant time scales and the generated pressure. (C) 2004 American Institute of Physics.