Aging in a simple model of a structural glass

We consider a simple model of a structural glass, represented by a lattice gas with kinetic constraints in contact with a particle reservoir. Quench below the glass transition is represented by the jump of the chernical potential above a threshold. After a quench, the density approaches the critical density—where the diffusion coefficient of the particles vanishes—following a power law in time. In this regime, the two-time self-correlation functions exhibit aging. The behavior of the model can be understood in terms of simple mean-field arguments