Spatial correlations in the dynamics of glassforming liquids: Experimental determination of their temperature dependence - Archive ouverte HAL Access content directly
Journal Articles Physical Review E : Statistical, Nonlinear, and Soft Matter Physics Year : 2007

Spatial correlations in the dynamics of glassforming liquids: Experimental determination of their temperature dependence

(1) , (2) , (1) , (3) , (4) , (5, 6) , (2, 6) , (2) , (7)
1
2
3
4
5
6
7

Abstract

We use recently introduced three-point dynamic susceptibilities to obtain an experimental determination of the temperature evolution of the number of molecules N corr that are dynamically correlated during the structural relaxation of supercooled liquids. We first discuss in detail the physical content of three-point functions that relate the sensitivity of the averaged two-time dynamics to external control parameters such as temperature or density, as well as their connection to the more standard four-point dynamic susceptibility associated with dynamical heterogeneities. We then demonstrate that these functions can be experimentally determined with good precision. We gather available data to obtain the temperature dependence of N corr for a large number of supercooled liquids over a wide range of relaxation time scales from the glass transition up to the onset of slow dynamics. We find that N corr systematically grows when approaching the glass transition. It does so in a modest manner close to the glass transition, which is consistent with an activation-based picture of the dynamics in glassforming materials. For higher temperatures, there appears to be a regime where N corr behaves as a power-law of the relaxation time. Finally, we find that the dynamic response to density, while being smaller than the dynamic response to temperature, behaves similarly, in agreement with theoretical expectations.
Fichier principal
Vignette du fichier
PhysRevE_76_041510.pdf (581.12 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

cea-01395180 , version 1 (10-11-2016)

Identifiers

Cite

C. Dalle-Ferrier, C. Thibierge, C. Alba-Simionesco, L. Berthier, G. Biroli, et al.. Spatial correlations in the dynamics of glassforming liquids: Experimental determination of their temperature dependence. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2007, 76, pp.041510. ⟨10.1103/PhysRevE.76.041510⟩. ⟨cea-01395180⟩
134 View
315 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More