Out of equilibrium dynamics of a single polymer chain

Vous êtes cordialement invités à la conférence de Paolo MALGARETTI, MPI for intelligent systems, Stuttgart, Germany, organisée par l'Institut Charles Sadron.

Résumé :

The dynamics of a single simple polymer chain has been know since quite a while. However,
when polymers are driven out of equilibrium novel regimes may arise.
In this contribution I will discuss two scenarios in which a simple polymer is driven out of
equilibrium by different means.
In the first part I will discuss the problem of polymer translocation across a varying section
channel. In particular, I will show that for smoothly varying channels and gentle external forces
the dynamics of the confined polymer can be mapped into that of a point-like particle in an
effective potential. This mapping provide a nice tool to investigate the dynamics of polymer is
such circumstances and in particular can explain the observed non-monotonous dependence
of polymer translocation current on polymer size.
In the second pat I will discuss the dynamics of a polymer made of "active" colloids, i.e. colloids
that, like microswimmers, can induce a net force on the backbone of the colloid. By means of
Brownian dynamics simulations I will show that the activity induces a coil-to-globule-like
transition and that the effective diffusion coefficient is strongly enhanced. In particular I will show
that this effect is maximum when the effective force generated by the active colloids is along the
backbone of the polymer and strongly diminishes when the force is assumed as isotropic.

Pour rencontrer le conférencier, veuillez prendre contact avec Hendrik Meyer, tél. 03 88 41 40 32 ou mail (hendrik.meyer@ics-cnrs.unistra.fr)