MODELING OF INTERFACES: APPLICATIONS IN SURFACE AND POLYMER PHYSICS

Abstract

In this dissertation, I give an overview of my work on multiscale modeling

of interfaces in crystalline and block-copolymer systems. I focus on two distinct

interface systems: steps on vicinal surfaces and microdomain interfaces in block-

copolymers melts. For each system, I consider how to (i) define the interface, (ii)

derive a coarse-grained model of the interface, and (iii) use the model to study

morphological features of the interface. For vicinal surfaces, we define a step by

means of ensemble averages, which leads to a Burton-Cabrera-Frank (BCF) -type

model of surface evolution. Using the BCF model, we study the combined effects of

step interactions and fluctuations. For block-copolymers, we define the microdomain

interfaces in terms of the relative density of monomers and use the Leibler-Ohta-

Kawasaki phase-field Hamiltonian to study the line-edge roughness.