2013/01/26 by Maksym Romenskyy, Vladimir Lobaskin · 40 citations
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Condensed matter physics #Correlation function (quantum field theory) #Critical exponent #Diffusion and Search Dynamics #Exponent #Function (biology) #Insect and Arachnid Ecology and Behavior #Measure (data warehouse) #Micro and Nano Robotics #Particle (ecology) #Phase (matter) #Phase transition #Physics #Quantum mechanics #Relaxation (psychology) #Statistical physics #Thermodynamics #Transition point #cond-mat.stat-mech #nlin.AO #physics.bio-ph
paper · pdf · doi:10.1140/epjb/e2013-30821-1
published in The European Physical Journal B 86(3) (Springer Science+Business Media) · Submitted to EPJ B
arxiv created 2013/01/26 · openalex publication_date 2013/03/01 · arxiv updated 2013/05/02 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study dynamic self-organisation and order-disorder transitions in a two-dimensional system of self-propelled particles. Our model is a variation of the Vicsek model, where particles align the motion to their neighbours but repel each other at short distances. We use computer simulations to measure the orientational order parameter for particle velocities as a function of intensity of internal noise or particle density. We show that in addition to the transition to an ordered state on increasing the particle density, as reported previously, there exists a transition into a disordered phase at the higher densities, which can be attributed to the destructive action of the repulsions. We demonstrate that the transition into the ordered phase is accompanied by the onset of algebraic behaviour of the two-point velocity correlation function and by a non-monotonous variation of the velocity relaxation time. The critical exponent for the decay of the velocity correlation function in the ordered phase depends on particle concentration at low densities but assumes a universal value in more dense systems.