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LS Tsimring

Publications and source records attributed to LS Tsimring.

11 recordsLinked to original sources

Patterns in thin vibrated granular layers: interfaces, hexagons, and superoscillons

A theoretical and experimental study of patterns in vibrated granular layers is presented. An order parameter model based on the parametric Ginzburg-Landau equation is used to describe strongly nonlinear excitations including hexagons, interfaces between flat antiphase domains, and new localized objects, superoscillons. The experiments confirm the existence of superoscillons and bound states of superoscillons and interfaces. On the basis of the order parameter model we predict analytically and confirm experimentally that additional subharmonic driving results in the controlled motion of interfaces.

Journal Article↗

Crystallization kinetics and self-induced pinning in cellular patterns

Within the framework of the Swift-Hohenberg model it is shown numerically and analytically that the front propagation between cellular and uniform states is determined by periodic nucleation events triggered by the explosive growth of the localized zero-eigenvalue mode of the corresponding linear problem. We derive an evolution equation for this mode using asymptotic analysis, and evaluate the time interval between nucleation events, and hence the front speed. In the presence of noise, we find the velocity exponent of "thermally activated" front propagation (creep) beyond the pinning threshold.

Journal Article↗