@article{BaltanasZaikinFeudeletal.2002, author = {Baltan{\´a}s, J. P. and Zaikin, Alexei A. and Feudel, Fred and Kurths, J{\"u}rgen and Sanjuan, Miguel Angel Fern{\´a}ndez}, title = {Noise-induced effects in tracer dynamics}, year = {2002}, language = {en} } @article{ZaikinTopajGarciaOjalvo2002, author = {Zaikin, Alexei A. and Topaj, Dmitri and Garcia-Ojalvo, Jordi}, title = {Noise-enhanced propagation of bichromatic signals}, year = {2002}, abstract = {We examine the influence of noise on the propagation of harmonic signals with two frequencies through discrete bistable media. We show that random fluctuations enhance propagation of this kind of signals for low coupling strengths, similarly to what happens with purely monochromatic signals. As a more relevant finding, we observe that the frequency being propagated with better efficiency can be selected by tuning the intensity of the noise, in such a way that for large noises the highest frequency is transmitted better than the lower one, whereas for small noises the reverse holds. Such a noise-induced frequency selection can be expected to exist for general multifrequency harmonic signals.}, language = {en} } @article{ZaikinGarciaOjalvoSchimanskyGeieretal.2002, author = {Zaikin, Alexei A. and Garc{\´i}a-Ojalvo, Jordi and Schimansky-Geier, Lutz and Kurths, J{\"u}rgen}, title = {Noise induced propagation in monostable media}, year = {2002}, abstract = {We show that external fluctuations are able to induce propagation of harmonic signals through monostable media. This property is based on the phenomenon of doubly stochastic resonance, where the joint action of multiplicative noise and spatial coupling induces bistability in an otherwise monostable extended medium, and additive noise resonantly enhances the response of the system to a harmonic forcing. Under these conditions, propagation of the harmonic signal through the unforced medium i observed for optimal intensities of the two noises. This noise-induced propagation is studied and quantified in a simple model of coupled nonlinear electronic circuits.}, language = {en} } @article{ZaikinLopezBaltanasetal.2002, author = {Zaikin, Alexei A. and L{\´o}pez, L and Baltan{\´a}s, J. P. and Kurths, J{\"u}rgen and Sanjuan, Miguel Angel Fern{\´a}ndez}, title = {Vibrational resonance in noise-induced structure}, year = {2002}, abstract = {We report on the effect of vibrational resonance in a spatially extended system of coupled noisy oscillators under the action of two periodic forces, a low-frequency one (signal) and a high-frequency one (carrier). Vibrational resonance manifests itself in the fact that for optimally selected values of high-frequency force amplitude, the response of the system to a low-frequency signal is optimal. This phenomenon is a synthesis of two effects, a noise- induced phase transition leading to bistability, and a conventional vibrational resonance, resulting in the optimization of signal processing. Numerical simulations, which demonstrate this effect for an extended system, can be understood by means of a zero-dimensional "effective" model. The behavior of this "effective" model is also confirmed by an experimental realization of an electronic circuit.}, language = {en} } @article{LandaZaikin2002, author = {Landa, Polina S. and Zaikin, Alexei A.}, title = {Fluctuational transport of a Brownian particle in ratchet-like gravitational potential field}, year = {2002}, language = {en} } @article{PikovskijZaikindelaCasa2002, author = {Pikovskij, Arkadij and Zaikin, Alexei A. and de la Casa, M. A.}, title = {System Size Resonance in Coupled Noisy Systems and in the Ising Model}, year = {2002}, abstract = {We consider an ensemble of coupled nonlinear noisy oscillators demonstrating in the thermodynamic limit an Ising-type transition. In the ordered phase and for finite ensembles stochastic flips of the mean field are observed with the rate depending on the ensemble size. When a small periodic force acts on the ensemble, the linear response of the system has a maximum at a certain system size, similar to the stochastic resonance phenomenon. We demonstrate this effect of system size resonance for different types of noisy oscillators and for different ensembles{\`u}lattices with nearest neighbors coupling and globally coupled populations. The Ising model is also shown to demonstrate the system size resonance.}, language = {en} }