Long range order in atomistic models for solids -

by Alessandro Giuliani (Università Roma TRE)

Wednesday 14 Apr 2021, 14:30 → 16:00 Europe/Rome

Seminario delle Meccaniche & Conferenza del Centro Linceo B.Segre

We consider a 3D model for an elastic crystal with continuous symmetry, previously introduced by Ariza and Ortiz. The model supports dislocation defects, including grains, and we show that iit correctly predicts the Read-Shockley law for the energy of a grain boundary. We analyze it in terms of a Gibbs distribution with energy function given by the Ariza-Ortiz Hamiltonian plus a contribution from dislocation cores. Our main result is that the model exhibits long range positional order at low temperatures. The proof is based on the tools of discrete exterior calculus, together with cluster expansion techniques. Joint work with F. Theil.

Link per il collegamento: https://meet.google.com/pip-kvzt-fkz