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Publications [#303631] of Robert P. Behringer
Papers Published
- Coulais, C; Behringer, RP; Dauchot, O, Contacts Dynamics Reveals Widom Lines for Jamming,
EPL, vol. 100
(February, 2012),
pp. 44005 [1202.5687v3], [doi]
(last updated on 2019/02/20)
Abstract: We experimentally study the vicinity of the Jamming transition by
investigating the statics and the dynamics of the contact network of an
horizontally shaken bi-disperse packing of photo-elastic discs. Compressing the
packing very slowly, while maintaining a mechanical excitation, yields a
granular glass, namely a frozen structure of vibrating grains. In this glass
phase, we observe a remarkable dynamics of the contact network, which exhibits
strong dynamical heterogeneities. Such heterogeneities are maximum at a packing
fraction $\phi^*$, \emph{distinct} and smaller than the jamming packing
fraction $\phi_J$, which is indicated by the abrupt variation of the average
number of contact per particle. We demonstrate that the two cross-overs, one
for the maximum dynamical heterogeneity, and the other for static jamming,
converge at point J in the zero mechanical excitation limit, a behavior
reminiscent of the Widom lines in the supercritical phase of a second order
critical point. Our findings are discussed in the light of recent numerical and
theoretical studies of thermal soft spheres.
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