Domain Growth in the Active Model B: Critical and Off-critical Composition

  title={Domain Growth in the Active Model B: Critical and Off-critical Composition},
  author={Sudipta Pattanayak and Shradha Mishra and Sanjay Puri},
  journal={Soft Materials},
  pages={286 - 296}
ABSTRACT We study the ordering kinetics of an assembly of active Brownian particles (ABPs) on a two-dimensional substrate. We use a coarse-grained equation for the composition order parameter ,where and denote space and time, respectively. The model is similar to the Cahn-Hilliard equation orModel B (MB) for a conserved order parameter with an additional activity term of strength . This model has been introduced by Wittkowski et al., Nature Comm. 5, 4351 (2014), and is termed Active Model B… 

Shearing effects on the phase coarsening of binary mixtures using the Active Model B

The phase separation of a two-dimensional active binary mixture is studied under the action of an applied shear through numerical simulations. It is highlighted how the strength of the external flow

Structure and dynamics in active matter systems

  • S. Das
  • Physics
    Soft Materials
  • 2021
Active matter systems are made of self-propelling particles and make ideal ground for studies of out-ofequilibrium phenomena. The self-propulsion is fueled by continuous drawing of energy from the



Phase-separation kinetics in a model with order-parameter-dependent mobility

We present extensive results from two-dimensional simulations of phase-separation kinetics in a model with order-parameter dependent mobility. We find that the time-dependent structure factor

Phase separation driven by surface diffusion: a Monte Carlo study.

A kinetic Ising model is proposed to study phase separation driven by surface diffusion and multispin coding techniques are used to develop fast algorithms for Monte Carlo simulations of Models B and S to study the late stages of pattern dynamics in these systems.

When are active Brownian particles and run-and-tumble particles equivalent? Consequences for motility-induced phase separation

Active Brownian particles (ABPs, such as self-phoretic colloids) swim at fixed speed v along a body-axis u that rotates by slow angular diffusion. Run-and-tumble particles (RTPs, such as motile

Enhanced dynamics of active Brownian particles in periodic obstacle arrays and corrugated channels

The periodic arrangement of the obstacles enhances the persistent motion of the ABP in comparison to its motion in the free space and induces directionality in ABP motion at late time.

Active colloidal propulsion over a crystalline surface

We study both experimentally and theoretically the dynamics of chemically self-propelled Janus colloids moving atop a two-dimensional crystalline surface. The surface is a hexagonally close-packed

Dynamic scaling of growing interfaces.

A model is proposed for the evolution of the profile of a growing interface that exhibits nontrivial relaxation patterns, and the exact dynamic scaling form obtained for a one-dimensional interface is in excellent agreement with previous numerical simulations.

Hydrodynamics of soft active matter

This review summarizes theoretical progress in the field of active matter, placing it in the context of recent experiments, and highlights the experimental relevance of various semimicroscopic derivations of the continuum theory for describing bacterial swarms and suspensions, the cytoskeleton of living cells, and vibrated granular material.

Active nematics on a substrate: Giant number fluctuations and long-time tails

We construct the equations of motion for the coupled dynamics of order parameter and concentration for the nematic phase of driven particles on a solid surface, and show that they imply i) giant

Collective transport for active matter run-and-tumble disk systems on a traveling-wave substrate.

Numerically the transport of an assembly of active run-and-tumble disks interacting with a traveling-wave substrate is examined and it is suggested that swarming or clustering motion can serve as a method by which an active system can collectively move against an external drift.

Scalar φ4 field theory for active-particle phase separation.

This work introduces 'Active Model B', a scalar φ(4) field theory (or phase-field model) that minimally violates detailed balance via a leading-order square-gradient term, and finds that this additional term has modest effects on coarsening dynamics, but alters the static phase diagram by creating a jump in (thermodynamic) pressure across flat interfaces.