Macroscopic facilitation of glassy relaxation kinetics: Ultrastable glass films with frontlike thermal response

The recent experimental fabrication of ultrastable glass films, via vapor deposition [Swallen , Science 315 , 353 (2007)] and the observation of frontlike response to the annealing of these films [Swallen , Phys. Rev. Lett. 102 , 065503 (2009)] have raised important questions about the possibility of manipulating the properties of glass films and addressing fundamental questions about kinetics and thermodynamics of amorphous materials. Central to both of these issues is the need to establish the essential physics that governs the formation of the ultrastable films and their subsequent response. In this paper, we demonstrate that a generic model of glassy dynamics can account for the formation of ultrastable films, the associated enhancement of relaxation rates by a factor of 10 5 , the observation of frontlike response to temperature jumps and the temperature dependence of the front velocity.