Competition between energy- and entropy-driven activation in glasses.

  title={Competition between energy- and entropy-driven activation in glasses.},
  author={Matthew R. Carbone and Marco Baity-Jesi},
  journal={Physical review. E},
  volume={106 2-1},
In simplified models of glasses we clarify the existence of two different kinds of coexisting activated dynamics, with one of the two dominating over the other. One is the energy barrier hopping that is typically used to understand activation, and the other, which we call entropic activation, is driven by the scarcity of convenient directions in phase space. When entropic activation dominates, the height of the energy barriers is no longer the primary factor governing the system's slowdown. In… 

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