title: Local Flow Field and Slip Length of Superhydrophobic Surfaces.
abstract: While the global slippage of water past superhydrophobic surfaces has attracted wide interest, the local distribution of slip still remains unclear. Using fluorescence correlation spectroscopy, we performed detailed measurements of the local flow field and slip length for water in the Cassie state on a microstructured superhydrophobic surface. We revealed that the local slip length is finite, nonconstant, anisotropic, and sensitive to the presence of surfactants. In combination with numerical calculations of the flow, we can explain all these properties by the local hydrodynamics.
authors.affiliation: Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Schäffel
authors.affiliation: Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
authors.forename: Kaloian
authors.initials: K
authors.lastname: Koynov
authors.affiliation: Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
authors.forename: Doris
authors.initials: D
authors.lastname: Vollmer
authors.affiliation: Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Butt
authors.affiliation: Max Planck Institute for Polymer Research, 55128 Mainz, Germany.
authors.forename: Clarissa
authors.initials: C
authors.lastname: Schönecker