title: Two-dimensional heterogeneous dynamics at the surface of a colloidal suspension.
abstract: We report on an x-ray photon correlation spectroscopy experiment investigating the surface structure and dynamics of colloidal particles suspended in a supercooled viscous liquid. The static structure factor in the direction parallel and perpendicular to the surface reveals a more disordered structure at the surface as compared to the bulk. The particles display heterogeneous ballistic dynamics parallel to the surface. The particle dynamics in the direction perpendicular to the surface is much slower and does not show the hallmarks of ballistic motion.
authors.affiliation: HASYLAB at DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Duri
authors.forename: T
authors.initials: T
authors.lastname: Autenrieth
authors.forename: L-M
authors.initials: LM
authors.lastname: Stadler
authors.forename: O
authors.initials: O
authors.lastname: Leupold
authors.forename: Y
authors.initials: Y
authors.lastname: Chushkin
authors.forename: G
authors.initials: G
authors.lastname: Grübel
authors.forename: C
authors.initials: C
authors.lastname: Gutt