# Loopy Lévy flights enhance tracer diffusion in active suspensions

@article{Kanazawa2020LoopyLF, title={Loopy L{\'e}vy flights enhance tracer diffusion in active suspensions}, author={Kiyoshi Kanazawa and Tomohiko G. Sano and Andrea Cairoli and Adrian Baule}, journal={Nature}, year={2020}, volume={579}, pages={364-367} }

Brownian motion is widely used as a model of diffusion in equilibrium media throughout the physical, chemical and biological sciences. However, many real-world systems are intrinsically out of equilibrium owing to energy-dissipating active processes underlying their mechanical and dynamical features 1 . The diffusion process followed by a passive tracer in prototypical active media, such as suspensions of active colloids or swimming microorganisms 2 , differs considerably from Brownian motion…

## 25 Citations

Rapid-prototyping a Brownian particle in an active bath.

- Medicine, PhysicsSoft matter
- 2020

A minimal model for experiment and theory covering the wide time and length scales of usual active matter systems and can be used as a stochastic dynamic simulator for Brownian objects in various active baths without mechanistic understanding.

Transport and diffusion enhancement in non-Gaussian correlated ratchets

- Physics
- 2021

Living cells are known to generate non-Gaussian active fluctuations that are significantly larger than thermal fluctuations owing to various metabolic activities. Understanding the effect of active…

Colossal Brownian yet non-Gaussian diffusion in a periodic potential: Impact of nonequilibrium noise amplitude statistics.

- Medicine, PhysicsChaos
- 2021

The influence of nonequilibrium noise amplitude statistics on the colossal Brownian, yet non-Gaussian diffusion is investigated by investigating the tail of amplitude distribution, which impacts both the magnitude of diffusion amplification and the Gaussianity of the position and increments statistics.

Transport and Diffusion Enhancement in Experimentally Realized Non-Gaussian Correlated Ratchets.

- MedicineThe journal of physical chemistry letters
- 2021

It is found that occasional kicks of an active Brownian ratchet comprising a colloidal particle in an optically generated asymmetric periodic potential driven by non-Gaussian noise having finite-amplitude active bursts, each arriving at random and decaying exponentially, are more efficient for transport and diffusion enhancement of the particle.

Distribution and pressure of active Lévy swimmers under confinement

- Physics
- 2021

Many active matter systems are known to perform Lévy walks during migration or foraging. Such superdiffusive transport indicates long-range correlated dynamics. These behavior patterns have been…

Anomalous Diffusion and Lévy Walks Distinguish Active from Inertial Turbulence.

- Medicine, PhysicsPhysical review letters
- 2021

It is shown that such dense active suspensions manifest superdiffusion, via Lévy walks, which masquerades as a crossover from ballistic to diffusive scaling in measurements of mean-squared displacements, and is tied to the emergence of hitherto undetected oscillatory streaks in the flow.

Active carpets drive non-equilibrium diffusion and enhanced molecular fluxes

- MedicineNature communications
- 2021

The enhanced diffusivity of molecules or passive particles are derived as a function of distance from an active carpet using Schnitzer's telegraph model and generalised Fick’s laws to elucidate certain non-equilibrium properties of active coating materials and life at interfaces.

Enhanced velocity fluctuations in interacting swimmer suspensions

- PhysicsJournal of Fluid Mechanics
- 2020

Abstract This paper characterizes the nature of velocity fluctuations in swimmer suspensions by determining the fluid velocity variance and the diffusivity of immersed passive tracers in dilute…

Extended Poisson-Kac theory: A unifying framework for stochastic processes with finite propagation velocity

- Computer Science, Physics
- 2020

Extended Poisson-Kac theory not only ensures by construction a mathematical representation of physical reality that is ontologically valid at all time and length scales, but also provides a toolbox of stochastic processes that can be used to model potentially any kind of finite velocity dynamical phenomena observed experimentally.

Optimization identification of superdiffusion processes in biology: an algorithm for processing observational data and a self-similar solution of the kinetic equation

- Biology, Physics
- 2020

The approximate self-similar solution for the parameters of step-length PDF and T is shown to provide reasonable accuracy of the space-time evolution of migrant's density.

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