Francesco Puosi

Learn More
We study stress time series caused by plastic avalanches in athermally sheared disordered materials. Using particle-based simulations and a mesoscopic elastoplastic model, we analyze system size and shear-rate dependence of the stress-drop duration and size distributions together with their average temporal shape. We find critical exponents different from(More)
The spatial correlations of the monomer displacements are studied via molecular-dynamics simulations of a melt of fully flexible, unentangled polymer chains with different length, interacting potential, density, and temperature. Both the scalar and the vector characters of the correlations are considered and their extension quantified in terms of suitable(More)
The slow relaxation, the diffusivity, and the fast cage-dynamics of a melt of fully flexible unentangled polymer chains is studied by molecular-dynamics simulations. States with different nonbonding potential, chain length, density and temperature are considered. The scaling between the slow dynamics and the fast dynamics, as characterized by the amplitude(More)
We describe in detail the model used in the manuscript and explain the our numerical implementation set to run in parallel on GPUs. We provide also some details about the post-processing and analysis of the raw simulation results. We study the scalar elasto-plastic model in two (2d) and three dimensions (3d) under the presence of an imposed shear-rate,(More)
We investigate by molecular-dynamics simulations, the fast mobility-the rattling amplitude of the particles temporarily trapped by the cage of the neighbors-in mildly supercooled states of dense molecular (linear trimers) and atomic (binary mixtures) liquids. The mixture particles interact by the Lennard-Jones potential. The non-bonded particles of the(More)
The universal scaling between the average slow relaxation/transport and the average picosecond rattling motion inside the cage of the first neighbors has been evidenced in a variety of numerical simulations and experiments. Here, we first show that the scaling does not need information concerning the arbitrarily-defined glass transition region and relies on(More)
The violation of the Stokes-Einstein (SE) law is investigated in a melt of linear chains by extensive molecular-dynamics simulations. It is found that the SE breakdown is signaled (with 5% uncertainty) by the monomer mean-square displacement <u(2)> on the picosecond time scale. On this time scale the displacements of the next-next-nearest neighbors are(More)
  • 1