変形する粒子のジャミング転移と固有振動

抄録

The jamming transition of soft particles has well been studied by physicists and the critical behavior of the pressure, elastic moduli, and excess coordination number has been examined by numerous experiments and simulations. In numerical studies of the jamming transition, molecular dynamics simulations play an important role in extracting critical exponents and analyzing normal modes. In most numerical simulations, however, the particles are not allowed to deform though real soft particles can be deformed by contacts with neighboring particles. Here, we theoretically and numerically investigate the jamming transition of deformable particles. Employing the Morse-Witten model, we derive the (extended) Hessian of soft deformable particles. We also use the Morse-Witten model for the force law in molecular dynamics simulations and numerically demonstrate mechanically stable packings of deformable particles. We find that the shear modulus and density of states of deformable particles are quantitatively different from those of artificially undeformed particles.