Professor XU Ning’s group from department of Physics in School of Physical Sciences discovered a novel jamming regime of amorphous systems. Their paper “New Jamming Scenario: From Marginal Jamming to Deep Jamming” was published in Physical Review Letters (PRL 106, 125503, 2011) on March 25.
Jamming describes the development of rigidity in amorphous systems. For instance, colloidal suspensions and granular materials jam into amorphous solids when they are so compact that no particles can move freely. In their paper, they study the properties of jammed packings of frictionless spheres over a wide range of volume fractions. They observe a crossover volume fraction which separates marginally jammed solids that have received many attentions in the past decade and a new type of amorphous solids that they properly refer to as deeply jammed solids. Deeply jammed solids exhibit surprisingly different behaviors from marginally jammed ones in the critical scalings, structures, and vibrations. This work opens a route to explore the new jamming phase deeply inside the jamming phase diagram and seek experimental realizations and applications of this novel type of amorphous systems.
This work was supported by the National Natural Science Foundation of China (No. 91027001) and startup grant from USTC.