Dislocation Dynamics in an Anisotropic Stripe Pattern

Abstract

The dynamics of dislocations confined to grain boundaries in a striped system are studied using electroconvection in the nematic liquid crystal N4. In electroconvection, a striped pattern of convection rolls forms for sufficiently high driving voltages. We consider the case of a rapid change in the voltage that takes the system from a uniform state to a state consisting of striped domains with two different wavevectors. The domains are separated by domain walls along one axis and a grain boundary of dislocations in the perpendicular direction. The pattern evolves through dislocation motion parallel to the domain walls. We report on features of the dislocation dynamics. The kinetics of the domain motion are quantified using three measures: dislocation density, average domain wall length, and the total domain wall length per area. All three quantities exhibit behavior consistent with power law evolution in time, with the defect density decaying as $t^{-1/3}$, the average domain wall length growing as $t^{1/3}$, and the total domain wall length decaying as $t^{-1/5}$. The two different exponents are indicative of the anisotropic growth of domains in the system.

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References in corpus (8)

• Theory of Phase Ordering Kinetics
• Domain Coarsening in Systems Far from Equilibrium
• Grain boundary pinning and glassy dynamics in stripe phases
• Pattern Dynamics of Rayleigh-Benard convective rolls and weakly segregated diblock copolymers
• Ordering kinetics of stripe patterns
• Defect Structures in the Growth Kinetics of the Swift-Hohenberg Model
• Domain Coarsening in Electroconvection
• Direct observation of twist mode in electroconvection in I52

Cited by in corpus (8)

• Growth of Order in An Anisotropic Swift-Hohenberg Model
• Grain boundary dynamics in stripe phases of non potential systems
• Coarsening in potential and nonpotential models of oblique stripe patterns
• Coarsening of Topological Defects in Oscillating Systems with Quenched Disorder
• Amplitude Modulation and Relaxation-Oscillation of Counterpropagating Rolls within a Broken-Symmetry Laser-Induced Electroconvection Strip
• Impact of noise on domain growth in electroconvection
• Strain and defects in oblique stripe growth
• Early time evolution of Freedericks patterns generated from states of electroconvection