Conferences - Seminars

  Monday 11 February 2019 14:00 - 15:30 BSP 407

An overview of universal avalanche statistics at the yielding transition of amorphous solids

By Ezequiel Ferrero

In the last years, several groups have described the yielding phenomenon in the deformation of amorphous materials from a statistical physics point of view. To that end, coarse-grained approaches to amorphous solids were introduced, the so-called elasto-plastic models (EPM) [1].
In this talk, I will focus on the statistics of avalanches produced by the characteristic stick-slip behavior close to the yielding transition, enquiring into its common properties among different EPM proposals. I will present in particular the less studied case of EPMs with stress-dependent transition rates for local yielding [2], which help us to see how "dynamical" exponents -those related to the driving speed- may depend on the model details while universality stands more robust for "static" critical exponents.
On the way, the current understanding of yielding from mean-field descriptions and comparison with the depinning transition of a driven elastic line in random media, will be briefly discussed. If time permits, I will further comment on the the strain-rate dependence [3] and inertial effects [4] on the statistics of avalanches as we depart, respectively, from the usually addressed quasistatic and overdamped limits.
[1] Deformation and flow of amorphous solids: a review of mesoscale elastoplastic models
A. Nicolas, E.E. Ferrero, K. Martens, J.-L. Barrat
Rev. Mod. Phys. 90, 045006 (2018)
[2] Static and dynamic critical exponents for elastoplastic models of amorphous solids
E.E. Ferrero and E.A. Jagla, (unpublished).
[3] Driving Rate Dependence of Avalanche Statistics and Shapes at the Yielding Transition
C. Liu, E.E. Ferrero, F. Puosi, J.-L. Barrat, and K. Martens
Phys. Rev. Lett. 116, 065501 (2016)
[4] Inertia and universality of avalanche statistics: The case of slowly deformed amorphous solids
K. Karimi, E.E. Ferrero, J.-L. Barrat
Phys. Rev. E 95, 013003 (2017)

Organization Matthieu Wyart

Contact Corinne Weibel

Accessibility General public

Admittance Free