A review on shear jamming

Jamming is a ubiquitous phenomenon that appears in many soft matter systems, including granular materials, foams, colloidal suspensions, emulsions, polymers, and cells — when jamming occurs, the system undergoes a transition from flow-like to solid-like states. Conventionally, the jamming transition occurs when the system reaches a threshold jamming density under isotropic compression, but recent studies reveal that jamming can also be induced by shear. Shear jamming has attracted much interest in the context of non-equilibrium phase transitions, mechanics and rheology of amorphous materials. Here we review the phenomenology of shear jamming and its related physics. We first describe basic observations obtained in experiments and simulations, and results from theories. Shear jamming is then demonstrated as a “bridge” that connects the rheology of athermal soft spheres and thermal hard spheres. Based on a generalized jamming phase diagram, a universal description is provided for shear jamming in frictionless and frictional systems. We further review the isostaticity and criticality of the shear jamming transition, and the elasticity of shear jammed solids. The broader relevance of shear jamming is discussed, including its relation to other phenomena such as shear hardening, dilatancy, fragility, and discrete shear thickening.