Mosaic multi-state scenario vs. one-state description of supercooled liquids
Département de Physique, Université de Rome La Sapienza
Lundi 29/01/2007, 14:15
Salle Claude Itzykson, Bât. 774, Orme des Merisiers
According to the mosaic scenario, relaxation in deeply supercooled liquids is ruled by two competing mechanisms: surface tension, opposing the creation of local excitations, and entropy, providing the drive to the configurational rearrangement of a given region. We test this scenario through numerical simulations well below the Mode Coupling temperature. Given an equilibrated configuration, we freeze all the particles outside a sphere and study the thermodynamics of this sphere. The frozen environment acts as a pinning field. By measuring the overlap between the unpinned and pinned equilibrium configurations of the sphere, we can see whether it has switched to a different state or not. We do not find any clear evidence of the mosaic scenario. Rather, our results seem compatible with the existence of one single state, the liquid. We do, however, find evidence of a growing static correlation length, which seems unrelated to the mosaic one.