Premalatha K, Chandrasekar V K, Senthilvelan M, Lakshmanan M
Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India.
Centre for Nonlinear Science & Engineering, School of Electrical & Electronics Engineering, SASTRA University, Thanjavur 613 401, Tamilnadu, India.
Phys Rev E. 2017 Feb;95(2-1):022208. doi: 10.1103/PhysRevE.95.022208. Epub 2017 Feb 10.
We show the existence of chimeralike states in two distinct groups of identical populations of globally coupled Stuart-Landau oscillators. The existence of chimeralike states occurs only for a small range of frequency difference between the two populations, and these states disappear for an increase of mismatch between the frequencies. Here the chimeralike states are characterized by the synchronized oscillations in one population and desynchronized oscillations in another population. We also find that such states observed in two distinct groups of identical populations of nonlocally coupled oscillators are different from the above case in which coexisting domains of synchronized and desynchronized oscillations are observed in one population and the second population exhibits synchronized oscillations for spatially prepared initial conditions. Perturbation from such spatially prepared initial condition leads to the existence of imperfectly synchronized states. An imperfectly synchronized state represents the existence of solitary oscillators which escape from the synchronized group in population I and synchronized oscillations in population II. Also the existence of chimera state is independent of the increase of frequency mismatch between the populations. We also find the coexistence of different dynamical states with respect to different initial conditions, which causes multistability in the globally coupled system. In the case of nonlocal coupling, the system does not show multistability except in the cluster state region.
我们展示了在两组全局耦合的相同斯图尔特 - 朗道振子群体中存在类嵌合态。类嵌合态仅在两组群体之间频率差的小范围内存在,并且随着频率失配的增加这些状态会消失。这里类嵌合态的特征是一组群体中振荡同步而另一组群体中振荡不同步。我们还发现,在两组非局部耦合的相同振子群体中观察到的此类状态与上述情况不同,在上述情况中,在一组群体中观察到同步和不同步振荡的共存区域,而对于空间准备的初始条件,另一组群体呈现同步振荡。来自这种空间准备初始条件的扰动导致不完全同步状态的存在。不完全同步状态表示存在从群体 I 中的同步组逃逸的孤立振子以及群体 II 中的同步振荡。此外,嵌合态的存在与群体之间频率失配的增加无关。我们还发现,对于不同的初始条件存在不同动力学状态的共存,这在全局耦合系统中导致多稳定性。在非局部耦合的情况下,除了在簇态区域外,系统不显示多稳定性。