Multiferroic Microstructure Created from Invariant Line Constraint

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Satyakam Kar - , Chair of Metallic Materials and Metal Physics, Leibniz Institute for Solid State and Materials Research Dresden, TUD Dresden University of Technology, Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • Yuki Ikeda - , Federal Institute for Materials Research and Testing Berlin (Author)
  • Kornelius Nielsch - , Chair of Metallic Materials and Metal Physics, Leibniz Institute for Solid State and Materials Research Dresden, TUD Dresden University of Technology (Author)
  • Heiko Reith - , Leibniz Institute for Solid State and Materials Research Dresden (Author)
  • Robert Maaß - , Federal Institute for Materials Research and Testing Berlin, University of Illinois at Urbana-Champaign, Technical University of Munich (Author)
  • Sebastian Fähler - , Helmholtz-Zentrum Dresden-Rossendorf (Author)

Abstract

Ferroic materials enable a multitude of emerging applications, and optimum functional properties are achieved when ferromagnetic and ferroelectric properties are coupled to a first-order ferroelastic transition. In bulk materials, this first-order transition involves an invariant habit plane, connecting coexisting phases: austenite and martensite. Theory predicts that this plane should converge to a line in thin films, but experimental evidence is missing. Here, the martensitic and magnetic microstructure of a freestanding epitaxial magnetic shape memory film is analyzed. It is shown that the martensite microstructure is determined by an invariant line constraint using lattice parameters of both phases as the only input. This line constraint explains most of the observable features, which differ fundamentally from bulk and constrained films. Furthermore, this finite-size effect creates a remarkable checkerboard magnetic domain pattern through multiferroic coupling. The findings highlight the decisive role of finite-size effects in multiferroics.

Details

Original languageEnglish
JournalAdvanced functional materials
Publication statusAccepted/In press - 2024
Peer-reviewedYes

Keywords

Keywords

  • epitaxial films, finite-size effects, magnetic shape memory alloys, martensite, multiferroics