Evidence of Growing Spatial Correlations at the Glass Transition from Nonlinear Response Experiments

C. Crauste-Thibierge (1, 2) , C. Brun (1, 2) , F. Ladieu (1, 2) , D. L’hôte (1, 3) , G. Biroli (4) , J-P. Bouchaud (5)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 IRAMIS - Institut Rayonnement Matière de Saclay (DRF)
3 SPHYNX - Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes
4 IPHT - Institut de Physique Théorique - UMR CNRS 3681
5 CFM - Capital Fund Management

The ac nonlinear dielectric response χ3(ω,T) of glycerol was measured close to its glass transition temperature Tg to investigate the prediction that supercooled liquids respond in an increasingly non-linear way as the dynamics slows down (as spin-glasses do). We find that χ3(ω,T) indeed displays several non trivial features. It is peaked as a function of the frequency ω and obeys scaling as a function of ωτ(T), with τ(T) the relaxation time of the liquid. The height of the peak, proportional to the number of dynamically correlated molecules Ncorr(T), increases as the system becomes glassy, and χ3 decays as a power-law of ω over several decades beyond the peak. These findings confirm the collective nature of the glassy dynamics and provide the first direct estimate of the T dependence of Ncorr.

Domaines: Physique [physics]

C. Crauste-Thibierge, C. Brun, F. Ladieu, D. L’hôte, G. Biroli, et al.. Evidence of Growing Spatial Correlations at the Glass Transition from Nonlinear Response Experiments. Physical Review Letters, 2010, 104, pp.165703. ⟨10.1103/PhysRevLett.104.165703⟩. ⟨cea-01394784⟩