What Determines the Yield Stress in Amorphous Solids?

A crucially important material parameter for all amorphous solids is the yield stress, which is the value of the stress for which the material yields to plastic flow when it is strained quasi-statically at zero temperature. It is difficult in laboratory experiments to determine what parameters of the inter-particle potential effect the value of the yield stress. Here we use the versatility of numerical simulations to study the dependence of the yield stress on the parameters of the inter-particle potential. We find a very simple dependence on the fundamental scales which characterize the repulsive and attractive parts of the potential respectively, and offer a scaling theory that collapses the data for widely different potentials and in different space dimensions.