Regensburg 2004 – wissenschaftliches Programm
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AKB: Biologische Physik
AKB 50: Poster Session "Biological Physics"
AKB 50.42: Poster
Freitag, 12. März 2004, 10:30–13:00, B
Linear response of a grafted semiflexible polymer to a uniform field — •Panayotis Benetatos1 and Erwin Frey1,2 — 1Hahn-Meitner-Institut, Abteilung Theorie, Berlin — 2Fachbereich Physik, Freie Universitaet, Berlin
We study the linear response of a semiflexible polymer to a uniform force field. We use the worm-like chain model and we consider a polymer which has one end grafted and the other free. In contrast to a force applied at the free end, the field introduces a nonlocal interaction along the polymer contour. Because of this nonlocality, using the free chain propagator (two-point orientational probability density) for the calculation of the linear response of the polymer extension in the direction of the field fails. We can apply the propagator method, however, in order to calculate the linear response of the end-point tangent vector orientation where locality is restored. We then use this result and make an Ansatz to obtain the linear response of the extension. Our analytic results are functions of the total contour length, the persistence length, and the orientation of the field. We discuss how the response to a field differs from that to a force.