Dresden 2017 – wissenschaftliches Programm
CPP 11.8: Vortrag
Montag, 20. März 2017, 17:00–17:15, ZEU 255
Dynamics of polymer chains in active fluids — •Jaeoh Shin and Vasily Zaburdaev — Max Planck Institutes für Physik komplexer Systeme, Dresden, Germany
While the dynamics of polymer chains in viscous fluids are well understood, the dynamics in active fluids, which are common in living systems, can be very different. Here we study the dynamics of polymer chains in fluids that contain active Brownian particles (ABPs) in 2D by using Brownian dynamics simulations. The ABPs can be trapped in concave regions of the polymer contour and thus can strongly affect the propulsion of the polymer. The polymer center of mass shows super-diffusive motion at short times and above the capturing time of the ABPs, it goes to normal diffusion with the diffusivity much larger than in the case of a passive viscous medium. Interestingly, the long time diffusivity shows a non-monotonous behavior as functions of both the chain length n and the bending stiffness κ. We analyze the chain conformation by looking at its Fourier modes and find that at the optimal length/ stiffness, the chain has preferentially bent conformations. Finally, we consider the barrier crossing of polymer chains in a double-well potential. The crossing times show a non-monotonous behavior as a function of n and κ due to the non-monotonous diffusivity. These findings can be instrumental for efficient sorting of polymer chains by their length and elastic properties.