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arXiv · 1709.04930

Low-temperature anomalies of a vapor deposited glass

Beatriz Seoane·Daniel R. Reid·Juan J. de Pablo·Francesco Zamponi
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Abstract

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 $T^*$, at which slow dynamics and enhanced heterogeneity emerge. Around $T^*$, localized defects become visible, leading to vibrational anomalies as compared to standard solids. We find that on average, $T^*$ 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.

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Beatriz Seoane, Daniel R. Reid, Juan J. de Pablo, Francesco Zamponi. 2017-09-14. Low-temperature anomalies of a vapor deposited glass. https://doi.org/10.1103/physrevmaterials.2.015602

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