title: Dynamics of a tethered polymer in shear flow.
abstract: The dynamics of a single polymer tethered to a solid surface in a shear flow was observed using fluorescently labeled DNA chains. Dramatic shear enhanced temporal fluctuations in the chain extension were observed. The rate of these fluctuations initially decreased for increasing shear rate gamma; and increased above a critical gamma;. Simulations revealed that these anomalous dynamics arise from a continual recirculating motion of the chain or cyclic dynamics. These dynamics arise from a coupling of the chain velocity in the flow direction to thermally driven fluctuations of the chain in the shear gradient direction.
authors.affiliation: Physico-Chimie Curie, 26 rue d'Ulm, 75248 Paris Cedex 05, France.
authors.forename: P S
authors.initials: PS
authors.lastname: Doyle
authors.forename: B
authors.initials: B
authors.lastname: Ladoux
authors.forename: J L
authors.initials: JL
authors.lastname: Viovy
mesh_terms: D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes; D018715:Microscopy, Video; D010507:Periodicity; D011108:Polymers / Q000737:chemistry*; D012212:Rheology; D013314:Stress, Mechanical
chemical_list: D005456:Fluorescent Dyes; D011108:Polymers; D004247:DNA