On-off Intermittency in Electrohydrodynamic Convection in Nematics Driven by Multiplicative Noise

On-off Intermittency in Stochastically Driven Electrohydrodynamic Convection in Nematics

On-o Intermittency in Stochastically Driven Electrohydrodynamic Convection in Nematics

We report on-oo intermittency in electroconvection of nematic liquid crystals driven by a dichotomous stochastic electric voltage. With increasing voltage amplitude we observe short bursts of spatially regular stripe patterns which interrupt laminar phases of undistorted director state. Near a critical value of the amplitude the distribution of the duration of laminar phases is governed over se...

Low-frequency noise controls on-off intermittency of bifurcating systems.

A bifurcating system subject to multiplicative noise can display on-off intermittency. Using a canonical example, we investigate the extreme sensitivity of the intermittent behavior to the nature of the noise. Through a perturbative expansion and numerical studies of the probability density function of the unstable mode, we show that intermittency is controlled by the ratio between the departur...

Amplification of weak signals and stochastic resonance via on-off intermittency with symmetry breaking.

Nonlinear dynamical systems possessing reflection symmetry have an invariant subspace in the phase space. The dynamics within the invariant subspace can be random or chaotic. As a system parameter changes, the motion transverse to the invariant subspace can lose stability, leading to on-off intermittency. Under certain conditions, the bursting behavior is symmetry breaking. We demonstrate the p...

Directed percolation criticality in turbulent liquid crystals.

We experimentally investigate the critical behavior of a phase transition between two topologically different turbulent states of electrohydrodynamic convection in nematic liquid crystals. The statistical properties of the observed spatiotemporal intermittency regimes are carefully determined, yielding a complete set of static critical exponents in full agreement with those defining the directe...