Name of Research Group:Soft Matter Physics Lab (SMPL)

Description of Research Group:Our research interests are the classical topics in the soft matter physics, including the wetting phenomena, the passive and active Brownian motion in confined space and the self-assembly away from equilibrium state.

Colloidal particles in the Hele-Shaw cell exhibit distinct dynamics due to the confinement. The interaction among the particles make the problem much complicated. The microscopic collision process between particles and the thinning fluid layer surrounded is intriguing in the confined 2D system. By using the thermal controlling, magnetic (electric) filed we play the games on the Brownian motion of the passive particles and active stochastic microswimmers.

Recently, we are employing the bacteria, E. Coli, to illustrate the hydrodynamic behavior in the microfluidic channels, and the run-tumble active random motion. We quantitatively measure the bacteria orientation responding to the surrounding fluid flow, especially when the mean velocity of the fluid is comparable with the swimming velocity of the bacteria. We are extremely attracted to the collective motion, active rheology of the bacteria in the limited slow Poisseuille flow in the microfluidic channels.

Meanwile, drying suspension on diverse substrates with varying conditions is another topic we are still working on. Wetting control by nanostructured semiconductor materials is dedicated to the drying pattern from the colloidal suspension. Pressure (high pressure/vacuum) and temperature (heating and frozen) are used to control the drying dynamics of drops with the complex fluid.

Team members Introduction:

张春贺  

研究兴趣：柔性链在细菌湍流中的形态演化

      柔性链在细菌湍流中的形态变化具有显著的非线性动力学特性，人们已经通过数值计算发现了柔性链在不同活性自驱动颗粒悬浮液中具有丰富的新形态变化特征。因此作为一类吸引人的生物湍流如细菌湍流中，柔性链的形貌、曲屈等动力学行为是一个开放且非常有趣的问题。观察单个柔性链的形态变化及演化规律，测定柔性链各序参量的时-空域统计与分析，并计算柔性链在细菌湍流中的有效持久长度，从而理解远离平衡态的细菌湍流统计物理特性。