Heterogeneous and homogeneous crystal nucleation in colloidal hard-sphere like microgels at low metastabilities

We studied the crystallization kinetics of the homogeneous bulk as well as of the heterogeneous wall crystallization in a colloidal hard sphere model system within the fluid crystal coexistence region. Using time resolved static light scattering and Bragg microscopy we determined several parameters characterizing the crystallization process (induction times, growth coefficients, nucleation rate densities, ... ). By performing further analysis according to classical nucleation theory we can show that wall crystallization is favored by a vanishing nucleation barrier height leading to the conclusion that a hard sphere crystal completely wets a structureless hard wall.