Bera P K, Majumdar S, Ouillon G, Sornette D, Sood A K
Department of Physics, Indian Institute of Science, Bangalore, Karnataka, 560012, India.
Raman Research Institute, Bangalore, Karnataka, 560080, India.
Nat Commun. 2020 Jan 7;11(1):9. doi: 10.1038/s41467-019-13790-2.
The flow behavior of soft materials below the yield stress can be rich and is not fully understood. Here, we report shear-stress-induced reorganization of three-dimensional solid-like soft materials formed by closely packed nematic domains of surfactant micelles and a repulsive Wigner glass formed by anisotropic clay nano-discs having ionic interactions. The creep response of both the systems below the yield stress results in angular velocity fluctuations of the shearing plate showing large temporal burst-like events that resemble seismic foreshocks-aftershocks data measuring the ground motion during earthquake avalanches. We find that the statistical properties of the quake events inside such a burst map on to the scaling relations for magnitude and frequency distribution of earthquakes, given by Gutenberg-Richter and Omori laws, and follow a power-law distribution of the inter-occurrence waiting time. In situ polarized optical microscopy reveals that during these events the system self-organizes to a much stronger solid-like state.
屈服应力以下软材料的流动行为丰富多样，尚未得到充分理解。在此，我们报告了由表面活性剂胶束紧密堆积的向列域形成的三维类固体软材料以及由具有离子相互作用的各向异性粘土纳米盘形成的排斥性维格纳玻璃的剪切应力诱导重组。这两种系统在屈服应力以下的蠕变响应导致剪切板的角速度波动，呈现出类似地震前震 - 余震数据中测量地震雪崩期间地面运动的大时间尺度突发状事件。我们发现，此类突发内地震事件的统计特性符合古登堡 - 里希特定律和大森定律给出的地震震级和频率分布的标度关系，并遵循事件间等待时间的幂律分布。原位偏振光学显微镜显示，在这些事件期间，系统自组织成一种更强的类固体状态。
