A variational approach to ferronematics with a stray field energy

Session Information

Location: amf. P7 | "Gheorghe Asachi" Technical University of Iași (TUIAȘI)
Day: 4. Thursday 18
Time: 11:30-11:50
Chairperson: Michele Ruggeri

Presentation Details

Presentation Type: Oral presentation
Title: A variational approach to ferronematics with a stray field energy
Abstract: Ferronematic materials are colloidal suspensions of magnetic particles in liq-
uid crystals. They are complex materials with potential applications in display
technologies, sensors, microfluidics devices, etc. We consider a model for fer-
ronematics in a 2D domain with a variational approach. The proposed free
energy of the ferronematic system depends on the Landau-de Gennes (LdG)
order parameter Q and the magnetization M, and incorporates the complex in-
teraction between the liquid crystal molecules and the magnetic particles in the presence of an external magnetic field Hext. The energy functional combines the Landau-de Gennes nematic energy density and energy densities from the theory of micromagnetics including (an approximation of) the stray field energy and energetic contributions from an external magnetic field. For the proposed ferronematic energy, we first prove the existence of an energy minimizer and then the uniqueness of the minimizer in certain parameter regimes. Secondly, we numerically compute stable ferronematic equilibria by solving the gradient flow equations associated with the proposed ferronematic energy. The numerical results show that the stray field influences the localization of the interior nematic defects and magnetic vortices.

Presenter

Ms Shilpa Dutta
University of Wuerzburg | Germany

Authors

1. Dutta, Shilpa | University of Wuerzburg
2. Dalby, James | King's College London
3. Majumdar, Apala | University of Manchester
4. Schloemerkemper, Anja | University of Wuerzburg