A continuum micromorphic approach to nematic liquid crystals is exploited in order to describe electro-magneto-elastic coupling effects. Nematic microdeformation is modeled by relating microinertia, electric dipole and quadrupole densities to microrotation. Accordingly, polarization and magnetization are obtained together with a constitutive law for magnetic induction. The coupled system of balance laws for linear and angular momentum and Maxwell’s equations is employed to model equilibrium for an homeotropic structure of a nematic layer subject to electric and magnetic fields, assuming strong anchoring on the layer’s boundaries. It is shown that the trivial solution of null deformation allows for a not uniform magnetic field in the presence of a not null applied electric potential. The magnetic field induced Freedericksz transition is derived obtaining a threshold value of magnetic field which depends on the electric potential. Numerical results show an hysteresis behavior of the deformation solution just behind the threshold field, which is compatible with a first order, magnetic induced transition.
|Titolo:||Electromagnetic coupling in nematic liquid crystals modeled as microcontinua|
|Data di pubblicazione:||2019|
|Appare nelle tipologie:||01.01 - Articolo su rivista|