Dewetting dynamics of helium films on cesiated surfaces

The nonwetting of liquid He-4 on Cs below approximate to 2 K is now well es tablished. However, there exist discrepancies between the measured contact angles and hysteresis at the phase transition of various groups. These are attributed to the influence of the underlying Cs surface. Little is known, however, about the morphology of this surface. There is also a lack of info rmation concerning the dewetting dynamics of metastable He-4 films and the dewetting process of He-4 drops on this weak binding surface Cs. We present results showing the influence of surface properties on the dewetting behav iour of these metastable films and discuss the scenario of dewetting of a m acroscopic helium drop. (C) 2000 Elsevier Science B.V. All rights reserved.