Effective medium theory for viscoelasticity of soft jammed solids

Abstract

The viscoelastic properties of soft jammed solids, such as foams, emulsions, and soft colloids, have been the subject of experiments, with particular interest in the anomalous viscous loss. However, a microscopic theory to explain these experimental results is still lacking. Here, we develop an effective medium theory that incorporates the effects of contact damping. The theory explains experimentally observed viscoelastic properties, particularly attributing the anomalous viscous loss to marginal stability in amorphous systems. This work establishes a microscopic theory for describing the impact of damping on soft jammed solids and their viscoelastic behaviors.