Coralie Brun | Searcharxiv

arXiv2017

Anisotropic super-attenuation of capillary waves on driven glass interfaces

Metrological AFM measurements are performed on the silica glass interfaces of photonic band-gap fibres and hollow capillaries. The freezing of attenuated out-of-equilibrium capillary waves during the drawing process is shown to result in a reduced surface roughness. The roughness attenuation with respect to the expected thermodynamical limit is determined to vary with the drawing stress following a power law. A striking anisotropic character of the height correlation is observed: glass surfaces thus retain a structural record of the direction of the flow to which the liquid was submitted.

cond-mat.soft↗

arXiv2012

Nonlinear dielectric susceptibilities in supercooled liquids: a toy model

The dielectric response of supercooled liquids is phenomenologically modeled by a set of Asymmetric Double Wells (ADW), where each ADW contains a dynamical heterogeneity of $N_{corr}$ molecules. We find that the linear macroscopic susceptibility $χ_1$ does not depend on $N_{corr}$ contrary to all higher order susceptibilities $χ_{2k+1}$. We show that $χ_{2k+1}$ is proportional to the $k^{th}$ moment of $N_{corr}$, which could pave the way for new experiments on glass transition. In particular, as predicted by Bouchaud and Biroli on general grounds [Phys. Rev. B, {\bf 72}, 064204 (2005)], we find that $χ_3$ is proportional to the average value of $N_{corr}$. We fully calculate $χ_3$ and, with plausible values of few parameters our model accounts for the salient features of the experimental behavior of $χ_3$ of supercooled glycerol.

cond-mat.soft↗