When a liquid droplet is put onto a surface, two situations distinguishable by the contact angle may result. If the contact angle is zero, the droplet spreads across the surface, a situation referred to as complete wetting. Second, if the contact angle is between 0° and 180°, the droplet does...

We present ellipsometry and interferrometry experiments which allow us to observe the transition point between the standard first-order wetting and the long-range critical wetting. Moreover we provide a direct measurement of the free-energy singularities in the sequential wetting scenario of...

When confining vacuum fluctuations between two identical walls, the Casimir force manifests itself as a mutual attraction of the walls. When confining concentration fluctuations of a binary liquid mixture, an analogous force should exist near the critical temperature TC; it is called the critical...

We study the vibrational spectrum and the low-energy modes of a three-dimensional colloidal crystal using confocal microscopy. This is done in a two-dimensional cut through a three-dimensional crystal. We find that the observed density of states is incompatible with the standard Debye form in...

Measurement of the resistance to a stretching motion, the so-called elongational viscosity ηe, has proven to be difficult for dilute polymer solutions, although it is important for a large number of applications. We attempt to deduce ηe of dilute solutions of flexible polymers in two different...

The spreading of Newtonian fluids onto smooth solid substrates is well known; the speed of the contact line is given by a competition between capillary driving forces and viscous dissipation, yielding Tanner's law R∝t1/10. Here, we study the spreading of droplets of complex fluids having...