# gst: anisotropic active depletion around a self-propelled non-interactive colloids; three characteristic states could be identified.

<< Active colloids in a bath of inert particles of smaller size cause anisotropic depletion. >>️

Here AA << combine mesoscale hydrodynamic simulation as well as theoretical analysis to examine the physical origin for the active depletion around a self-propelled noninteractive colloid. >>️

Their << results elucidate that the variable hydrodynamic effect critically governs the microstructure of the depletion zone. Three characteristic states of anisotropic depletion are identified, depending on the strength and stress of activity. >>️

<< Furthermore, (AA) demonstrate that such depletion in nonequilibrium results in various clusters with ordered organization of squirmers, which follows a distinct principle contrary to that of the entropy scenario of depletion in equilibrium. >>

️

Lijun Dai, Haixiao Wan, et al. Hydrodynamic Anisotropy of Depletion in Nonequilibrium. Phys. Rev. Lett. 131, 134002. Sep 27, 2023. 

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.134002

Also: particle, colloids, in https://www.inkgmr.net/kwrds.html

Keywords: gst, particles, colloids, depletion, squirmers, self-propulsion systems

# gst: emergence of self-organizing zigzag patterns among (magnetic) particles suspended in a liquid

<< When molecules or bacteria organize into a long-range pattern, researchers want to understand how the microscopic interactions lead to the macroscopic order. (AA) observed such self-organization in magnetic particles suspended in a liquid and subjected to an oscillating magnetic field. Through experiments and simulations, the team showed that the resulting zigzag pattern is explained by the fluid flow generated around the oscillating particles, not by any details of the particles or the applied field. Similar zigzag patterns have also been seen in charged colloids subjected to oscillating electric fields, so the explanation may cover a range of particle systems. The researchers also believe that understanding and controlling the effect could lead to useful applications in microfluidics devices. >>️

David Ehrenstein. Self-Organized Zigzags from Fluid Flow. Physics 16, 138. Aug 11, 2023.

https://physics.aps.org/articles/v16/138

Gaspard Junot, Marco De Corato, Pietro Tierno. Large Scale Zigzag Pattern Emerging from Circulating Active Shakers. Phys. Rev. Lett. 131, 068301. Aug 11, 2023. 

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.068301

Also: particle, self-assembly, chiral, behav, in: https://www.inkgmr.net/kwrds.html  

Keywords: gst, behavior, particle, self-assembly, self-organization, chiral, active shakers, squirmers, alternating chirality