Low-temperature anomalies of a vapor deposited glass

We investigate the low temperature properties of two-dimensional Lennard-Jones glass films, prepared in silico both by liquid cooling and by physical vapor deposition. We identify deep in the solid phase a crossover temperature $T^{\ast }$, at which slow dynamics and enhanced heterogeneity emerge. Around $T^{\ast }$, localized defects become visible, leading to vibrational anomalies as compared to standard solids. We find that on average, $T^{\ast }$ decreases in samples with lower inherent structure energy, suggesting that such anomalies will be suppressed in ultra-stable glass films, prepared both by very slow liquid cooling and vapor deposition.