Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, China.
Chaos. 2009 Sep;19(3):033133. doi: 10.1063/1.3224034.
It has long been observed in experiments that frozen state of spiral waves can spontaneously appear in both excitable and oscillatory media, in which several spiral waves coexist and are well separated by thin walls (shocks). In this work, we study the global structure of frozen state of spiral waves in excitable media and find that different from stationary shocks in oscillatory media, in excitable media the shock dynamics actually depends on the status of single spiral, which is also determined by the system parameter, i.e., the shock line can be stationary if the single spiral is rigidly rotating, whereas it can wiggle if the single spiral is meandering, and the wiggling amplitude increases with the degree of meandering. We also find the stationary structure of shock line can still be well predicted by a previous theory, which has been developed for the frozen state of spiral waves in oscillatory media. All these findings are generic and expected to be verified in experiments.
长期以来,实验观察到在激活动力学和振荡介质中都可以自发出现螺旋波的冻结态,其中几个螺旋波共存并被薄壁(激波)很好地分隔开来。在这项工作中,我们研究了激活动力学中螺旋波冻结态的全局结构,发现与振荡介质中的固定激波不同,激波动力学实际上取决于单个螺旋的状态,这也由系统参数决定,即如果单个螺旋是刚性旋转的,则激波线可以是静止的,而如果单个螺旋是蜿蜒的,则激波线可以抖动,并且抖动幅度随着蜿蜒程度的增加而增加。我们还发现,一个以前为振荡介质中螺旋波的冻结态开发的理论仍然可以很好地预测激波线的静止结构。所有这些发现都是普遍的,预计可以在实验中得到验证。