Phys. Rev. Research 2, 023321 (2020) - Hidden velocity ordering in dense suspensions of self-propelled disks

The present paper studies the spontaneous velocity alignment and the time-intermittency of the kinetic-energy in dense phases of active matter. The dynamical properties are described by considering the spatial velocity correlations and constructing a non-equilibrium phase diagram of active force and density which explores homogeneous and inhomogeneous phases