Zhang Jiajun, Yuan Zhanjiang, Wang Junwei, Zhou Tianshou
School of Mathematics and Computational Science, Sun Yat-Sen University, Guangzhou, China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Feb;77(2 Pt 1):021101. doi: 10.1103/PhysRevE.77.021101. Epub 2008 Feb 5.
Stochastic coherence (SC) and self-induced stochastic resonance (SISR) are two distinct mechanisms of noise-induced coherent motion. For interacting SC and SISR oscillators, we find that whether or not phase synchronization is achieved depends sensitively on the coupling strength and noise intensities. Specifically, in the case of weak coupling, individual oscillators are insensitive to each other, whereas in the case of strong coupling, one fixed oscillator with optimal coherence can be entrained to the other, adjustable oscillator (i.e., its noise intensity is tunable), achieving phase-locking synchronization, as long as the tunable noise intensity is not beyond a threshold; such synchronization is lost otherwise. For an array lattice of SISR oscillators, except for coupling-enhanced coherence similar to that found in the case of coupled SC oscillators, there is an optimal network topology degree (i.e., number of coupled nodes), such that coherence and synchronization are optimally achieved, implying that the system-size resonance found in an ensemble of noise-driven bistable systems can occur in coupled SISR oscillators.
随机相干性（SC）和自诱导随机共振（SISR）是噪声诱导相干运动的两种不同机制。对于相互作用的SC和SISR振荡器，我们发现是否实现相位同步敏感地取决于耦合强度和噪声强度。具体而言，在弱耦合情况下，各个振荡器彼此不敏感，而在强耦合情况下，只要可调噪声强度不超过阈值，具有最佳相干性的一个固定振荡器就可以被另一个可调振荡器（即其噪声强度是可调的）所牵引，实现锁相同步；否则这种同步就会丢失。对于SISR振荡器的阵列晶格，除了类似于耦合SC振荡器情况下发现的耦合增强相干性之外，还存在一个最佳网络拓扑度（即耦合节点的数量），使得相干性和同步性能够得到最佳实现，这意味着在噪声驱动双稳系统集合中发现的系统规模共振可以在耦合的SISR振荡器中发生。
