2-loop Functional Renormalization for elastic manifolds pinned by disorder in N dimensions
Pierre Le Doussal, Kay Jörg Wiese
CNRS-Laboratoire de Physique Théorique de
l'Ecole Normale Supérieure,
24 rue Lhomond, 75005 Paris, France
Abstract
We study elastic manifolds in a
N-dimensional random potential using functional RG. We extend to
N>1 our previous construction of a field theory renormalizable
to two loops. For isotropic disorder with O(N) symmetry we obtain the
fixed point and roughness exponent to next order in ε=4-d, where
d is the internal dimension of the manifold. Extrapolation to the
directed polymer limit d=1 allows some handle on the strong coupling
phase of the equivalent N-dimensional KPZ growth equation, and
eventually suggests an upper critical dimension of about 2.5.
cond-mat/0501315 [pdf]
Phys. Rev. E 72 (2005) 035101 (R) [pdf]
Copyright (C) by Kay Wiese. Last edited March 17, 2008.