Non-quantum chirality in a driven Brusselator

We report the discovery of non-quantum chirality in the a periodically driven Brusselator. In contrast to standard chirality from quantum contexts, this novel type of chirality is governed by rate equations, namely by purely classical equations of motion. The Brusselator chirality was found by computing high-resolution phase diagrams depicting the number of spikes, local maxima, observed in stable periodic oscillations of the Brusselator as a function of the frequency and amplitude of the external drive. We also discuss how to experimentally observed non-quantum chirality in generic oscillators governed by nonlinear sets of rate equations.

Воздействие гармонического сигнала на генератор квазипериодических колебаний Анищенко-Астахова

A harmonic effect on a modified Anishchenko-Astakhov generator capable of demonstrating two-frequency quasi-periodic oscillations in the autonomous mode is considered. The possibility of doubling the three-frequency tori in a non-autonomous system is shown. The possibility of the effect of chaos suppression by an external signal is demonstrated, which leads not only to periodic, but also to quasi-periodic modes when the influence amplitude exceeds a certain threshold.

Wire network behaviour of superconducting films with lower symmetrical mesoscopic hole arrays

Superconducting films with the same hole density but different geometric symmetry have been designed and fabricated. The R(H) curves show obvious periodic oscillations with several dips at fractional matching fields. It is found that the period of the oscillations in the low field is not necessary equal to that derived from the hole density, but consistent with that from the corresponding wire networks when the large disk-like film regions are regarded as nodes. The experimental results of R(H), T c (H) and j c (H) at fractional matching fields within the first oscillation also support the rationality of considering films with large-diametered hole arrays as wire networks. Our results demonstrate that the connectivity of superconducting films with large-diametered hole arrays plays a more important role in the oscillations of R(H) curves.

Arousal elevation drives the development of oscillatory vocal output

Adult behaviors, such as vocal production, often exhibit temporal regularity. In contrast, their immature forms are more irregular. We ask whether the coupling of motor behaviors with arousal changes give rise to temporal regularity and drive the transition from variable to regular motor output over the course of development. We used marmoset monkey vocal production to explore this putative influence of arousal on the nonlinear changes in their developing vocal output patterns. Based on a detailed analysis of vocal and arousal dynamics in marmosets, we put forth a general model incorporating arousal and auditory-feedback loops for spontaneous vocal production. Using this model, we show that a stable oscillation can emerge as the baseline arousal increases, predicting the transition from stochastic to periodic oscillations occurring in marmoset vocal development. We further provide a solution for how this model can explain vocal development as the joint consequence of energetic growth and social feedback. Together, our model offers a plausible mechanism for the development of arousal-mediated adaptive behavior.

Quasi-Periodic Oscillations of Roll System in Corrugated Rolling Mill in Resonance

This paper investigates quasi-periodic oscillations of roll system in corrugated rolling mill in resonance. The two-degree of freedom vertical nonlinear mathematical model of roller system is established by considering the nonlinear damping and nonlinear stiffness within corrugated interface of corrugated rolling mill. In order to investigate the quasi-periodic oscillations at the resonance points, the Poincaré map is established by solving the power series solution of dynamic equations. Based on the Poincaré map, the existence and stability of quasi-periodic oscillations from the Neimark-Sacker bifurcation in the case of resonance are analyzed. The numerical simulation further verifies the correctness of the theoretical analysis.

Modulation Characteristics of Period-One Oscillations in Quantum Cascade Lasers

Quantum cascade lasers subject to tilted optical feedback produce periodic oscillations, quasi-periodic oscillations, and low-frequency oscillations. This work presents the modulation characteristics of period-one (P1) oscillations in a quantum cascade laser with tilted optical feedback. The electrical signal at the oscillation frequency is more than 50 dB higher than the noise level, and the electrical linewidth is less than 2.0 kHz. This electrical linewidth is about four orders of magnitude narrower than the optical linewidth (around 16 MHz) of the free-running laser, which suggests that the optical sidebands induced by the P1 oscillations are highly coherent with the main optical mode. In addition, the modulation depth of the optical signal is found to be in the range of 1% to 3.5%. In addition, it is verified in the simulations that the P1 oscillations induce not only amplitude modulation but also frequency modulation due to the phase-amplitude coupling effect.