Glassy Dynamics Under Superhigh Pressure
Abstract
Nearly all glass-forming liquids feature, along with the structural alpha-relaxation process, a faster secondary process (beta-relaxation), whose nature belongs to the great mysteries of glass physics. However, for some of these liquids, no well-pronounced secondary relaxation is observed. A prominent example is the archetypical glass-forming liquid glycerol. In the present work, by performing dielectric spectroscopy under superhigh pressures up to 6 GPa, we show that in glycerol a significant secondary relaxation peak appears in the dielectric loss at P > 3 GPa. We identify this beta-relaxation to be of Johari-Goldstein type and discuss its relation to the excess wing. We provide evidence for a smooth but significant increase of glass-transition temperature and fragility on increasing pressure.
Cite
@article{arxiv.0911.3496,
title = {Glassy Dynamics Under Superhigh Pressure},
author = {A. A. Pronin and M. V. Kondrin and A. G. Lyapin and V. V. Brazhkin and A. A. Volkov and P. Lunkenheimer and A. Loidl},
journal= {arXiv preprint arXiv:0911.3496},
year = {2010}
}
Comments
5 pages, 5 figures, final version with minor changes according to referee demands and corrected Figs 1 and 2