From Marginal Jamming To Deep Jamming

Soft matter gives strong nonlinear responses to very small perturbation, which is driven by the entropy, not by the internal energy of the system. The jamming phase diagram successfully grasps the commonalities of different kinds of soft matter, and thus puts them into one framework to research their complex and flexible properties. Jamming is a concept to describe the process during which liquid transforms into amorphous solids. There are three ways to achieve jammed materials: increasing the density, lowering the temperature or decreasing the stress. For short-rang repulsive interactions, there is a special point named Point J at zero temperature and zero shear stress, around which various anomalous properties of jammed solids have been studied. However, it has not yet been questioned whether these properties would persist when the volume fraction is far away from Point J. In this thesis, numerical simulation methods were used to analyze the scalings, structure and vibrational properties of jammed solids at zero temperature and zero shear stress but over a wide range of pressure (corresponding to different volume fractions). Surprisingly, there exists a unique volume faction (about 1.18) which significantly separates deep jammed solids from marginally jammed solids. Therefore, the value of this project is to find a new class of amorphous solids, and to open a new branch of jamming research, deep jamming.