Nonlinear behavior and fluctuation-induced dynamics in the photosensitive Belousov-Zhabotinsky reaction
Publication Year
2017
Type
Journal Article
Abstract
The photosensitive Belousov-Zhabotinsky (pBZ) reaction has been used extensively to study the properties of chem. oscillators. In particular, recent experiments revealed the existence of complex spatiotemporal dynamics for systems consisting of coupled micelles (V < 10-21 L) or droplets (V ≈ [10-8-10-11] L) in which the pBZ reaction takes place. These results have been mostly understood in terms of reaction-diffusion models. However, in view of the small size of the droplets and micelles, large fluctuations of concentrations are to be expected. In this work, the role is investigated of fluctuations on the dynamics of a single droplet with stochastic simulations of an extension of the Field-Koros-Noyes (FKN) model taking into account the photosensitivity. The birhythmicity and chaotic behaviors predicted by the FKN model in the absence of fluctuations become transient or intermittent regimes whose lifetime decreases with the size of the droplet. Simple oscillations are more robust and can be observed even in small systems (V > 10-12 L), which justifies the use of deterministic models in microfluidic systems of coupled oscillators. The simulations also reveal that fluctuations strongly affect the efficiency of inhibition by light, which is often used to control the kinetics of these systems: oscillations are found for parameter values for which they are supposed to be quenched according to deterministic predictions.
Keywords
Journal
Phys. Chem. Chem. Phys.
Volume
19
Pages
22528-22537
ISBN
1463-90841463-9076
CAplus AN 2017:1277942; MEDLINE PMID: 28809962 (Journal; Article)