Avalanche structural rearrangements in cold dusty plasma liquids through cascaded coherent excitations of heterogeneous multiscale thermal acoustic waves

Abstract

Microscopically, the cold liquid around freezing consists of crystalline ordered domains supporting thermally excited acoustic wave turbulence. Whether and how the above uncertain multiscale waves can lead to uncertain avalanche microstructure rearrangements in the form of multiscale clusters, and identifying their precursors, are elusive fundamental issues. Here, using a cold quasi-two-dimensional dusty plasma liquid as a platform, we experimentally address the above issues, especially the extreme avalanche activities, by correlating avalanche dynamics with the spatiotemporal evolutions of local structural order, defects, and the local amplitudes and phases of various wave modes. It is found that the preceding larger skeleton of poor structural order around more and widely spread defects can facilitate the later sequential multiscale wave excitations from slow to fast modes and their cascaded intermittent phase synchronizations for bond-breaking/reconnection and structural rearrangements. It is the key for the onset, spreading with defect propagation, and termination of the large avalanche cluster.