Equilibrium and non-equilibrium wetting phenomena of the liquid Se–Tl system on a silica substrate

We studied the wetting phenomena of liquid Se–Tl on a silica substrate, not only in the thermal equilibrium state but in non-equilibrium states created by a temperature gradient and a temperature jump. In the thermal equilibrium state, no apparent critical point wetting was observed, but a lowering of temperature apart from the critical temperature induced a wetting transition, and the surface was covered with a Se-rich film. This result cannot be explained by the Cahn’s critical point wetting theory. When the surface of the cell is heated up compared to the bulk, a transition from the wetting to non-wetting state is observed. In addition, we observed that a temporal wetting state is induced by a sudden decrease of temperature.