title: Honeycomb and triangular domain wall networks in heteroepitaxial systems.
abstract: A comprehensive study is presented for the influence of misfit strain, adhesion strength, and lattice symmetry on the complex Moiré patterns that form in ultrathin films of honeycomb symmetry adsorbed on compact triangular or honeycomb substrates. The method used is based on a complex Ginzburg-Landau model of the film that incorporates elastic strain energy and dislocations. The results indicate that different symmetries of the heteroepitaxial systems lead to distinct types of domain wall networks and phase transitions among various surface Moiré patterns and superstructures. More specifically, the results show a dramatic difference between the phase diagrams that emerge when a honeycomb film is adsorbed on substrates of honeycomb versus triangular symmetry. It is also shown that in the small deformation limit, the complex Ginzburg-Landau model reduces to a two-dimensional sine-Gordon free energy form. This free energy can be solved exactly for one dimensional patterns and reveals the role of domains walls and their crossings in determining the nature of the phase diagrams.
authors.affiliation: Department of Physics, Oakland University, Rochester, Michigan 48309, USA.
authors.forename: K R
authors.initials: KR
authors.lastname: Elder
authors.affiliation: Department of Physics, Oakland University, Rochester, Michigan 48309, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Applied Physics and COMP Centre of Excellence, Aalto University School of Science, P.O. Box 11000, FI-00076 Aalto, Finland.
authors.forename: K L M
authors.initials: KL
authors.lastname: Elder
authors.affiliation: Department of Applied Physics and COMP Centre of Excellence, Aalto University School of Science, P.O. Box 11000, FI-00076 Aalto, Finland.
authors.forename: P
authors.initials: P
authors.lastname: Hirvonen
authors.affiliation: Department of Physics, University of Swaziland, Private Bag 4, Kwaluseni, Swaziland.
authors.forename: S K
authors.initials: SK
authors.lastname: Mkhonta
authors.affiliation: Department of Physics, Brown University, P.O. Box 1843, Providence, Rhode Island 02912, USA.
authors.forename: S-C
authors.initials: SC
authors.lastname: Ying
authors.affiliation: Department of Physics, Brown University, P.O. Box 1843, Providence, Rhode Island 02912, USA.
authors.forename: E
authors.initials: E
authors.lastname: Granato
authors.affiliation: Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48201, USA.
authors.forename: Zhi-Feng
authors.initials: ZF
authors.lastname: Huang
authors.affiliation: Department of Applied Physics and COMP Centre of Excellence, Aalto University School of Science, P.O. Box 11000, FI-00076 Aalto, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Ala-Nissila