Real-space phase field investigation of evolving magnetic domains and twin structures in a ferromagnetic shape memory alloy

H. H. Wu; A. Pramanick; Y. B. Ke; X.-L. Wang

doi:10.1063/1.4967531

Author(s)

H. H. Wu
A. Pramanick
Y. B. Ke
X.-L. Wang

Detail(s)

Original language	English
Article number	183904
Journal / Publication	Journal of Applied Physics
Volume	120
Issue number	18
Online published	14 Nov 2016
Publication status	Published - 14 Nov 2016

Link(s)

DOI	DOI https://doi.org/10.1063/1.4967531 Final Published version
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Attachment(s)	Documents 11831283.pdf Final Published version, 4.12 MB, PDF Publisher's Copyright Statement This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in H. H. Wu, A. Pramanick, Y. B. Ke, and X.-L. Wang, "Real-space phase field investigation of evolving magnetic domains and twin structures in a ferromagnetic shape memory alloy", Journal of Applied Physics 120, 183904 (2016) and may be found at https://doi.org/10.1063/1.4967531.
Link to Scopus	https://www.scopus.com/record/display.uri?eid=2-s2.0-84995761625&origin=recordpage
Permanent Link	https://scholars.cityu.edu.hk/en/publications/publication(a441e453-64e4-494c-93c6-7014d64bcb0f).html

Abstract

A real-space phase field model combining Landau-Lifshitz-Gilbert equation and time-dependent Ginzburg-Landau equation is developed to investigate the evolution of ferromagnetic domains and martensitic twin structures in a ferromagnetic shape memory alloy at different lengthscales. Both domain and twin structures are obtained by simultaneously solving for minimization of magnetic, elastic, and magnetoelastic coupling energy terms via a nonlinear finite element method. The model is applied to simulate magneto-structural evolution within a nanoparticle and a bulk single-crystal of the alloy Ni₂MnGa, which are subjected to mechanical strains. It is shown that a nanoparticle contains magnetic vortex structures within a single twin variant, whereas for a bulk crystal both 90° and 180° domain structures are present within multiple twin variants.