Seminarium Fizyki Materii Skondensowanej

If colloidal particles get trapped at a fluid-fluid interface they interacteffectively via deformations of the interface. These so-called capillary in-teractions can easily be tuned by changing external fields and they dependsensitively on the shape of the particles. This makes them good candidatesfor designing self-assembling systems and provides a convenient experimental playground for studying basic issues of statistical mechanics in two dimensions in the presence of long-ranged interactions [1]. On the other hand, recent experiments [2] show that capillary forces can have important consequences for stabilizing so-called Pickering emulsions, which are formed by particle-covered droplets (e.g., oil) in a solvent (e.g., water). Whereas considerable theoretical progress has been made in understanding capillary interactions at flat interfaces, basic issues such as the balance of forces acting on the interface and the influence of the incompressibility of the liquid enclosed by spherical interfaces have not yet been fully resolved. In the seminar I will present analytical and numerical results of the detailed calculations of the effective interaction potentials between particles trapped at the surface of free [3] or sessile [4-5] liquid droplets and discuss their consequences for formation of interfacial colloidal structures.[1] A. Dominguez, M. Oettel and S. Dietrich, Phys. Rev. E 82, 011402 (2010)[2] B. Madivala, J. Fransaer and J. Vermant, Langmuir 25, 2718 (2009)[3] J. Guzowski, M. Tasinkevych, S. Dietrich, Phys. Rev. E 84, 031401 (2011)[4] J. Guzowski, M. Tasinkevych, S. Dietrich, Eur. Phys. J. E 33, 219 (2010)[5] J. Guzowski, M. Tasinkevych, S. Dietrich, Soft Matter 7, 4189 (2011)