Guo Z B, Wang Y H, Xu S K
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China.
Phys Rev E. 2020 Mar;101(3-1):030201. doi: 10.1103/PhysRevE.101.030201.
Phase synchronization is a universal concept in macro- and microstate coupling of complex systems. In this Rapid Communication, we demonstrate the existence of phase synchronization dynamics in a wave-particle interaction process under the framework of a Vlasov-Poisson (VP) system. Starting from a random phase setup, it is shown that the phases of the electrons spontaneously develop coherent patterns in its velocity space. The most interesting finding is that, mediated by the long-wavelength electrostatic mode, the phases of the electrons tend to attract each other, condense into a mean phase, and form a chimera pattern. Due to the finite-time singularity of the mean phase, the phase pattern gets evaporated and recondenses into a different chimera pattern. For the scenario of a finite wavelength, the random phases rapidly condense to slashing lines, which become steeper and steeper through a sequence of evaporation-condensation processes. The slashing pattern drives the mixing of the distribution function in the velocity space, which then induces the damping of the electrostatic mode. This phase self-organization dynamics uncovers another aspect of wave-particle interaction physics, and sheds light onto the longstanding enigma of Landau damping.
相位同步是复杂系统宏观和微观状态耦合中的一个通用概念。在这篇快速通讯中，我们展示了在弗拉索夫 - 泊松（VP）系统框架下的波 - 粒子相互作用过程中存在相位同步动力学。从随机相位设置开始，研究表明电子的相位在其速度空间中自发地形成了相干模式。最有趣的发现是，在长波长静电模式的介导下，电子的相位倾向于相互吸引，凝聚成一个平均相位，并形成一种奇异子模式。由于平均相位的有限时间奇点，相位模式会蒸发并重新凝聚成不同的奇异子模式。对于有限波长的情况，随机相位迅速凝聚成斜线，这些斜线通过一系列蒸发 - 凝聚过程变得越来越陡峭。斜线模式驱动速度空间中分布函数的混合，进而导致静电模式的阻尼。这种相位自组织动力学揭示了波 - 粒子相互作用物理学的另一个方面，并为长期存在的朗道阻尼之谜提供了线索。
