Communications in Mathematical Physics
, Volume 279, Issue 1, pp 117146
First online:
The Effect of Disorder on Polymer Depinning Transitions
 Kenneth S. AlexanderAffiliated withDepartment of Mathematics KAP108, University of Southern California Email author
Rent the article at a discount
Rent now* Final gross prices may vary according to local VAT.
Get AccessAbstract
We consider a polymer, with monomer locations modeled by the trajectory of a Markov chain, in the presence of a potential that interacts with the polymer when it visits a particular site 0. We assume that probability of an excursion of length n is given by \(n^{c}\varphi(n)\) for some 1 < c < 2 and slowly varying \(\varphi\) . Disorder is introduced by having the interaction vary from one monomer to another, as a constant u plus i.i.d. mean0 randomness. There is a critical value of u above which the polymer is pinned, placing a positive fraction (called the contact fraction) of its monomers at 0 with high probability. To see the effect of disorder on the depinning transition, we compare the contact fraction and free energy (as functions of u) to the corresponding annealed system. We show that for c > 3/2, at high temperature, the quenched and annealed curves differ significantly only in a very small neighborhood of the critical point—the size of this neighborhood scales as \(\beta^{1/(2c3)}\), where β is the inverse temperature. For c < 3/2, given \(\epsilon > 0\), for sufficiently high temperature the quenched and annealed curves are within a factor of \(1\epsilon\) for all u near the critical point; in particular the quenched and annealed critical points are equal. For c = 3/2 the regime depends on the slowly varying function \(\varphi\).
 Title
 The Effect of Disorder on Polymer Depinning Transitions
 Journal

Communications in Mathematical Physics
Volume 279, Issue 1 , pp 117146
 Cover Date
 200804
 DOI
 10.1007/s0022000804255
 Print ISSN
 00103616
 Online ISSN
 14320916
 Publisher
 SpringerVerlag
 Additional Links
 Topics
 Industry Sectors
 Authors

 Kenneth S. Alexander ^{(1)}
 Author Affiliations

 1. Department of Mathematics KAP108, University of Southern California, Los Angeles, CA, 900892532, USA