Time-delayed feedback control of coherence resonance chimeras.

Area of Science:

• Nonlinear dynamics
• Complex networks
• Computational neuroscience

Background:

• Chimera states, where coherence and incoherence coexist in networks, are a key phenomenon in nonlinear dynamics.
• Noise-induced chimera states, specifically coherence resonance chimeras, have been observed in excitable systems.
• Understanding factors that control these states is crucial for network dynamics.

Purpose of the Study:

• To investigate the effect of time-delayed feedback on noise-induced chimera states in a FitzHugh-Nagumo network model.
• To explore the control capabilities of time-delayed feedback on the parameter range of coherence resonance chimeras.
• To identify and characterize novel chimera states induced by specific feedback delay regimes.

Main Methods:

• Utilized a FitzHugh-Nagumo system model operating in the excitable regime.
• Implemented a network with nonlocal coupling to study chimera states.
• Introduced and systematically varied time-delayed feedback to analyze its influence.

Main Results:

• Demonstrated that time-delayed feedback can effectively control the parameter range for the occurrence of coherence resonance chimeras.
• Identified a new dynamical regime, termed period-two coherence resonance chimera, under specific feedback delay conditions.
• Showcased the potential of time-delayed feedback as a control mechanism for complex network dynamics.

Conclusions:

• Time-delayed feedback is a significant factor in modulating noise-induced chimera states in nonlocally coupled networks.
• The discovered period-two coherence resonance chimera state offers new insights into complex oscillatory behaviors.
• This study highlights the utility of feedback control in manipulating emergent phenomena in excitable systems.