Poisson ratio and excess low-frequency vibrational states in glasses - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue The Journal of Chemical Physics Année : 2013

Poisson ratio and excess low-frequency vibrational states in glasses

Résumé

In glass, starting from a dependence of the Angell's fragility on the Poisson ratio [V. N. Novikov and A. P. Sokolov, Nature 431, 961 (2004)], and a dependence of the Poisson ratio on the atomic packing density [G. N. Greaves et al., Nat. Mater. 10, 823 (2011)], we propose that the heterogeneities are predominantly density fluctuations in strong glasses (lower Poisson ratio) and shear elasticity fluctuations in fragile glasses (higher Poisson ratio). Because the excess of low-frequency vibration modes in comparison with the Debye regime (boson peak) is strongly connected to these fluctuations, we propose that they are breathing-like (with change of volume) in strong glasses and shear-like (without change of volume) in fragile glasses. As a verification, it is confirmed that the excess modes in the strong silica glass are predominantly breathing-like. Moreover, it is shown that the excess breathing-like modes in a strong polymeric glass are replaced by shear-like modes under hydrostatic pressure as the glass becomes more compact.
Fichier principal
Vignette du fichier
poisson3.pdf (254.31 Ko) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-00852203 , version 1 (20-08-2013)

Identifiants

Citer

Eugène Duval, Thierry Deschamps, Lucien Saviot. Poisson ratio and excess low-frequency vibrational states in glasses. The Journal of Chemical Physics, 2013, 139, pp.064506. ⟨10.1063/1.4817778⟩. ⟨hal-00852203⟩
246 Consultations
173 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More