DIRECTOR FIELD OF DISCLINATION LINE IN UNIAXIAL NEMATIC LIQUID CRYSTAL IN THE PRESENCE OF MAGNETIC FIELD

Using the Oseen–Zöcher–Frank theory, in the steady state, I study the distortion energy of a disclination line in nematic liquid crystal in the presence of an external magnetic field. The director field around a disclination line is exactly calculated by minimizing the total free energy. The behavior of total free energy as a function of magnetic field for two kinds of nematic material (positive and negative magnetic anisotropy) are discussed. In the short distance limit, the total free energy per unit length is calculated. In this case, the magnetic dependence of total free energy is discussed.

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Monte Carlo Simulation of the Director Field of a Nematic Liquid Crystal with Three Elastic Coefficients

Zeitschrift für Naturforschung A ◽

10.1515/zna-1996-1-201 ◽

1996 ◽

Vol 51 (1-2) ◽

pp. 1-9 ◽

Cited By ~ 41

Author(s):

T. Gruhn ◽

S. Hess

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Free Energy ◽

Liquid Crystal ◽

External Field ◽

Boundary Conditions ◽

Nematic Liquid Crystal ◽

Director Field ◽

Fixed Boundary ◽

Elastic Coefficients

Abstract In this article, a Monte Carlo simulation is presented, which generates the equilibrium director field of a nematic liquid crystal under the influence of an external field and fixed boundary conditions. The liquid crystal is characterized by a set of directors on a spatially fixed lattice. The simulation is based on an expression for the Frank free energy with three elastic coefficients. The chosen discretisation conserves the nematic symmetry, which means n and - n are equivalent. The results for several Frederiks geometries with homogeneous and spatially modulated external fields are shown, as well as an investigation of a capillary with homeotropic boundary conditions. Further we compare our method with the Lebwohl-Lasher model and introduce an extension of the latter which distinguishes between splay-, twist-and bend-configurations.

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Pattern Formation in a Twisted Nematic Liquid Crystal Cell under an External Magnetic Field

Journal de Physique II ◽

10.1051/jp2:1996180 ◽

1996 ◽

Vol 6 (2) ◽

pp. 235-253 ◽

Cited By ~ 3

Author(s):

Luca Carlotti ◽

Sandro Faetti ◽

Maurizio Nobili

Keyword(s):

Magnetic Field ◽

Liquid Crystal ◽

External Magnetic Field ◽

Pattern Formation ◽

Nematic Liquid Crystal ◽

Liquid Crystal Cell ◽

Crystal Cell ◽

Twisted Nematic ◽

Twisted Nematic Liquid Crystal

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Dynamics of a disc in a nematic liquid crystal

Soft Matter ◽

10.1039/c5sm02333e ◽

2016 ◽

Vol 12 (4) ◽

pp. 1279-1294 ◽

Cited By ~ 11

Author(s):

Alena Antipova ◽

Colin Denniston

Keyword(s):

Magnetic Field ◽

Liquid Crystal ◽

Numerical Simulations ◽

Nematic Liquid Crystal ◽

Weak Magnetic Field ◽

Angular Speed ◽

The Magnetic Field

We explain the motion of a micron-sized ferromagnetic disc immersed in a nematic liquid crystal under the action of a weak magnetic field using numerical simulations. We show that the disc's behaviour can be controlled by the angular speed of the magnetic field and its magnitude.

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