Résumé
Phys. Rev. E 90, 052305 (2014) We use large scale computer simulations of a glass-forming liquid in which a
fraction c of the particles has been permanently pinned. We find that the
relaxation dynamics shows an exponential dependence on c. This result can be
rationalized by means of a simple theoretical Ansatz and we discuss its
implication for thermodynamic theories for the glass-transition. For
intermediate and low temperatures we find that the slowing down of the dynamics
due to the pinning saturates and that the cooperativity decreases with
increasing c, results which indicate that in glass-forming liquids there is a
dynamic crossover at which the shape of the relaxing entities changes.