Entropic force of polymers on a cone tip
Mohammad F. Maghrebi1a, Yacov Kantor2 and Mehran Kardar1
Department of Physics, Massachusetts Institute of Technology - Cambridge, MA 02139, USA
2 Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University - Tel Aviv 69978, Israel
Accepted: 24 October 2011
We consider polymers attached to the tip of a cone, and the resulting force due to entropy loss on approaching a plate (or another cone). At separations shorter than the polymer radius of gyration Rg, the only relevant length scale is the tip-plate (or tip-tip) separation h, and the entropic force is given by . The universal amplitude can be related to (geometry dependent) correlation exponents of long polymers. We compute for phantom polymers, and for self-avoiding (including star) polymers by ϵ-expansion, as well as by numerical simulations in 3 dimensions.
PACS: 64.60.F- – Equilibrium properties near critical points, critical exponents / 82.35.Lr – Physical properties of polymers / 05.40.Fb – Random walks and Levy flights
© EPLA, 2011