Stepwise melting of a model glass former under confinement

摘要: The equilibrium thermodynamics of a binary Lennard-Jones model glass former are investigated using exchange Monte Carlo simulations, covering the crystalline and amorphous regions configuration space in appropriate temperature ranges. We investigate both bulk film mixtures, latter being confined between noninteracting flat walls. Both systems exhibit principal heat capacity peak at melting point, but confinement leads to significant depression by about 25%. Microcanonical caloric curves, as well analysis probability distributions bond-orientational order parameter, show that this transition has first-order character. However, system shows additional features lower temperatures, which interpreted terms localized partial melting, perpendicular confining walls near walls, with some increase layering. This premelting is associated local minima on underlying potential energy surface not supported system.