We study the effects of rapid periodic and stochastic modulations of parameters in systems described by the complex parametric Ginzburg-Landau equation. Amplitude equations, which govern the dynamics of the field averaged over the rapid modulations, are derived. For temporal modulations of the linear detuning the threshold for the transition from Ising to Bloch walls is shifted depending on the strength of the perturbation. In contrast to this, rapid perturbations of the linear gain lead only to a decrease of the amplitude of both wall types leaving the bifurcation point of the Ising-Bloch transition unchanged. Stochastic perturbations of the detuning lead to a Brownian motion of the Bloch wall beyond bifurcation where the velocity is given analytically. All theoretical predictions are confirmed by numerical simulations of the full stochastic Ginzburg-Landau equation.
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http://dx.doi.org/10.1103/PhysRevE.71.056205 | DOI Listing |
Nanotechnology
January 2025
Department of Mechanical and Materials Engineering, Wright State University, Dayton, OH 45431, United States of America.
Surface-induced crystallization/amorphization of a Germanium-antimony-tellurium nanolayer is investigated using the phase field model. A Ginzburg-Landau (GL) equation introduces an external surface layer (ESL) within which the surface energy and elastic properties are adequately distributed. Next, the coupled GL and elasticity equations for the crystallization/ amorphization are solved.
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Ecole Centrale de Lyon, CNRS, Université Claude Bernard Lyon 1, INSA Lyon, LMFA, UMR5509, 69130 Ecully, France.
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Institut für Theoretische Physik, Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany.
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October 2024
School of Physical Sciences, Jawaharlal Nehru University, New Delhi-110067, India.
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November 2024
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