Enhanced pulse propagation in nonlinear arrays of oscillators

Journal Article · Mon Nov 01 04:00:00 EST 1999 · Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

DOI:https://doi.org/10.1103/PhysRevE.60.5317· OSTI ID:690727

Sarmiento, A; Reigada, R; Romero, A H; Lindenberg, K ^[1]

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1. Department of Chemistry and Biochemistry 0340, University of California at San Diego, La Jolla, California 92093-0340 (United States)

The propagation of a pulse in a nonlinear array of oscillators is influenced by the nature of the array and by its coupling to a thermal environment. For example, in some arrays a pulse can be speeded up while in others a pulse can be slowed down by raising the temperature. We begin by showing that an energy pulse (one dimension) or energy front (two dimensions) travels more rapidly and remains more localized over greater distances in an isolated array (microcanonical) of hard springs than in a harmonic array or in a soft-springed array. Increasing the pulse amplitude causes it to speed up in a hard chain, leaves the pulse speed unchanged in a harmonic system, and slows down the pulse in a soft chain. Connection of each site to a thermal environment (canonical) affects these results very differently in each type of array. In a hard chain the dissipative forces slow down the pulse while raising the temperature speeds it up. In a soft chain the opposite occurs: the dissipative forces actually speed up the pulse, while raising the temperature slows it down. In a harmonic chain neither dissipation nor temperature changes affect the pulse speed. These and other results are explained on the basis of the frequency vs energy relations in the various arrays. {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 690727
• Journal Information: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics Journal Issue: 5 Vol. 60; ISSN PLEEE8; ISSN 1063-651X
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ANHARMONIC OSCILLATORS
FLUCTUATIONS
HARMONIC OSCILLATORS
OSCILLATIONS
OSCILLATORS
PULSES
TEMPERATURE DEPENDENCE
THERMAL EQUILIBRIUM