Nonequilibrium phase transitions in a driven sandpile model

Abstract

We construct a driven sandpile slope model and study it by numerical simulations in one dimension. The model is specified by a threshold slope σ_c, a parameter α , governing the local current-slope relation (beyond threshold), and j_in, the mean input current of sand. A nonequilibrium phase diagram is obtained in the α -j_in plane. We find an infinity of phases, characterized by different mean slopes and separated by continuous or first-order boundaries, some of which we obtain analytically. Extensions to two dimensions are discussed.