Computing optimal interfacial structure of modulated phases

TL;DR

This paper introduces a computational framework for determining the optimal interfacial structures between two modulated phases, leveraging a box setup with boundary conditions aligned to bulk structures, and applies it to the Landau-Brazovskii model.

Contribution

The paper presents a general method for computing interfacial structures between modulated phases, incorporating boundary conditions and basis functions aligned with bulk structures, and demonstrates its application to complex phases.

Findings

Stable interfacial structures identified through free energy minimization.

Application to Landau-Brazovskii model reveals novel interfacial configurations.

Ordered modulated structures facilitate stabilization of interfaces.

Abstract

We propose a general framework of computing interfacial structures between two modulated phases. Specifically we propose to use a computational box consisting of two half spaces, each occupied by a modulated phase with given position and orientation. The boundary conditions and basis functions are chosen to be commensurate with the bulk structures. It is observed that the ordered nature of modulated structures stabilizes the interface, which enables us to obtain optimal interfacial structures by searching local minima of the free energy landscape. The framework is applied to the Landau-Brazovskii model to investigate interfaces between modulated phases with different relative positions and orientations. Several types of novel complex interfacial structures are obtained from the calculations.