Unidirectional single mode lasing realization and temperature induced mode switching in asymmetric GaN coupled cavities

Effective lasing mode control and unidirectional coupling of semiconductor microlasers are vital to boost their applications in optical interconnects, on-chip communication and bio-sensors. In this paper, symmetric and asymmetric GaN...

Dynamic Analysis and Synchronization with Unidirectional Coupling Involving Energy of a HR Neuron Under Electric Field and Memristive Autapse

Reliable neuron models play an important role in identifying the electrical activities, global bifurcation patterns, and dynamic mechanisms of neurons in complex electromagnetic environments. Considering the memristive autapse involving magnetic coupling has voltage-controlled, nonlinear, and memory, a 5-D HR neuron model containing magnetic field and electric field variables is established. Detailedly, the existence and stability conditions of the equilibrium point are determined by theoretical analysis, and the complex time-varying stability, saddle-node bifurcation, and Hopf bifurcation behaviors of the model are verified by numerical calculation. Interestingly, the system has a bistable structure consisting of quiescent state and period-1 and period-2 bursting modes near the subcritical Hopf bifurcation. It is noteworthy that the memristive autapse has a complex regulation mechanism for the bistable region so that three kinds of bistable coexisting structures and counterintuitive dynamic phenomena can be induced by appropriately adjusting the memristive autapse. Accordingly, the mechanism of positive feedback memristive autapse decreases its firing frequency, while negative feedback memristive autapse promotes its excitability was revealed by the fast-slow dynamic analysis. Extensive numerical results display that the system generally possesses period-adding bifurcation modes and comb-shaped chaotic structures. Furthermore, it is found that the firing modes and multistability regions of the system can be accurately predicted by analyzing the global dynamic behaviors of Hamilton energy. Importantly, it is verified that the unidirectional coupling controller involving energy is far more efficient and consumes less energy than electrical synaptic coupling in achieving complete synchronization with mismatched parameters.

Chaos Modulation Using Synchronization in Quantum Dot Light Emitting Diode with Optoelectronic Feedback

In this research, a communication scheme of chaos modulation (CMO) that depending on two chaotic quantum dot light emitting diodes (QDLEDs) synchronization was evaluated using theoretical model. The perturbation in behavior of the QDLED can be significantly increased by optoelectronic feedback. Changing the coupling strength between the transmitter and receiver in unidirectional coupling greatly contributes to creating a state of total synchronization between the two systems. Furthermore, the proposed communication model was successful by effectively receiving messages.

Клонирование химерных состояний в двухслойной сети бистабильных генераторов с запаздывающей обратной связью

Cloning of chimera states is for the first time studied in a two-layer network of identical bistable radio engineering generators with time-delayed feedback. The cases of mutual and unidirectional coupling between the network layers are considered. It is shown that for the cloning of chimera states it is necessary to choose the initial conditions of generators in a certain way.

Communication in Quantum Dot Light Emitting Diode with Optoelectronic Feedback Technique

A communication scheme based on the synchronization of two chaotic quantum dot light emitting diodes is theoretically examined. The Chaos in the quantum dot light emitting is generated by means of a positive optoelectronic feedback technique. Synchronization of the chaos is achieved by varying coupling strength between the transmitter and the receiver as unidirectional coupling. We then test a proposed chaos shift keying communication scheme by successfully transmitting messages.

Cellular Synchronisation through Unidirectional and Phase-Gated Signalling

Multiple natural and artificial oscillator systems achieve synchronisation when oscillators are coupled. The coupling mechanism, essentially the communication between oscillators, is often assumed to be continuous and bidirectional. However, the cells of the presomitic mesoderm synchronise their gene expression oscillations through Notch signalling, which is intermittent and directed from a ligand-presenting to a receptor-presenting cell. Motivated by this mode of communication we present a phase-gated and unidirectional coupling mechanism. We identify conditions under which it can successfully bring two or more oscillators to cycle in-phase. In the presomitic mesoderm we observed the oscillatory dynamics of two synchronizing cell populations and record one population halting its pace while the other keeps undisturbed, as would be predicted from our model. For the same system another important prediction, convergence to a specific range of phases upon synchronisation is also confirmed. Thus, the proposed mechanism accurately describes the coordinated oscillations of the presomitic mesoderm cells and provides an alternative framework for deciphering synchronisation.