Ken Elder - Honeycomb and Triangular Domain Wall Networks in Heteroepitaxial Systems
Wigner Szfi Szeminárium
(Oakland University, vendéglátó: Gránásy László)
"Honeycomb and Triangular Domain Wall Networks in Heteroepitaxial Systems"
Időpont: 2015. szeptember 15. (kedd) 10:00 (1 óra)
Hely: MTA Wigner FK SZFI, I. épület 1. emeleti Tanácsterem
In this talk I would like to present a study of the influence of misfit strain, adhesion strength, and lattice symmetry on the complex Moire patterns that form in ultrathin films adsorbed on compact triangular surfaces, such as graphene on metals. The approach here is based on a complex Ginzburg-Landau model of the film that incorporates elastic strain energy and dislocations. The results indicate that the different symmetries of the heteroepitaxial systems lead to distinct type of domain wall networks and phase transitions among various surface Moire patterns and superstructures. In addition, one of the commensurate-incommensurate phase transitions is observed to change from continuous to discontinuous at large strains, indicating a breakdown of continuum approaches at large strains due to the discreteness of the film lattice.
Részletes információ: http://www.szfki.hu/seminar