Internship: Memory of a disordered solid in a fluctuating environment

Due to their out-of-equilibrium nature, glassy materials (but also suspensions or fabrics) keep a memory of their thermal and mechanical past. In recent years it could be shown that such disordered solids could keep the memory of a previous oscillatory driving. Carefully designed experimental and numerical read-out protocols are able to retrieve the amplitude and direction of the training protocol. It turns out that such memory effects still persist for random driving protocols, e.g. when the shear cycles are replaced by a random walk. We would like to study in more details the memory behavior of disordered solids submitted to a fluctuating environment and see how it depends on the spatio-temporal properties of the driving protocols.

Here we propose to use a minimal model at mesoscopic scale to study the memory effects of glassy solids. More specifically, we plan to study the behavior of a simple elastoplastic lattice model which belong to the larger family of depinning models. Such models are based on the coupling between a stochastic dynamics at local scale and long- range elastic interactions. In the spirit as Ising-like models for magnetism or shell models for turbulence they are easy to implement numerically but rich enough to reproduce the critical behavior (avalanches, finite size effects) and the complex phenomenology of amorphous plasticity (hardening, shear-banding).

Expected skills: good computing skills and a taste for statistical physics, mechanics and soft matter.

[1] D. Kumar, S. Patinet, C.E. Maloney, D. Vandembroucq and M. Mungan, Mapping out the glassy landscape of a mesoscopic elastoplastic model, J. Chem. Phys. 157, 174504 (2022)
[2] D. Kumar, M. Mungan, S. Patinet and D. Vandembroucq, Self-organization and memory in a cyclically driven elasto-plastic model of an amorphous solid, arXiv:2409.07621 (2024)
[3] M. Mungan, D. Kumar, S. Patinet and D. Vandembroucq, Self-organization and memory in an amorphous solid subject to random loading, arXiv:2409.17096 (2024)