title: Recent Developments in Fully Fluctuating Field-Theoretic Simulations of Polymer Melts and Solutions.
abstract: We review the latest developments in computational methods for direct simulation of fully fluctuating field theories of polymeric assemblies. In this context, we describe a newly developed theoretical and computational framework for accurately computing fluctuation-corrected phase diagrams of mesostructured polymer systems and report the first such complete phase diagram for a diblock copolymer melt. The method is based on complex Langevin sampling of a UV regularized field-theoretic model, with Helmholtz free energies computed using thermodynamic integration. UV regularization ensures that the free energies do not have an arbitrary reference; they can be compared between incommensurate phases, permitting for the first time the computation of order-order transitions with fluctuation corrections. We further demonstrate that computed free energies are accurate in the disordered phase by comparison to perturbation theory on the one-loop level. Importantly, we note that our method uses no uncontrolled approximations beyond the initial definition of a coarse-grained molecular model for the polymer melt or solution. The method can be applied straightforwardly to melts and solutions containing multiple species with diverse polymer architectures.
authors.affiliation: Materials Research Laboratory, University of California , Santa Barbara, California 93106, United States.
authors.forename: Kris T
authors.initials: KT
authors.lastname: Delaney
authors.affiliation: Materials Research Laboratory, University of California , Santa Barbara, California 93106, United States.|Departments of Materials and Chemical Engineering, University of California , Santa Barbara, California 93106, United States.
authors.forename: Glenn H
authors.initials: GH
authors.lastname: Fredrickson