Collective motion of active particles exhibiting non-reciprocal orientational interactions

Scientific Reports, Journal Year: 2022, Volume and Issue: 12(1)

Published: Nov. 14, 2022

Abstract We present a Brownian dynamics study of 2D bath active particles interacting among each other through usual steric interactions and, additionally, via non-reciprocal avoidant orientational interactions. motivate them by the fact that two flagella alga Chlamydomonas interact sterically with nearby surfaces such torque acts on alga. As expected, in most cases disrupt motility-induced particle clustering baths. Surprisingly, however, we find can self-organize into collectively moving flocks if range is close to observe flocking motion manifest itself variety structural forms, spanning from single dense bands multiple moderately-dense stripes, which are highly dynamic. The order parameter found be only weakly dependent underlying flock structure. Together variance local-density distribution, one clearly group separate band and dynamic-stripes states.

Language: Английский

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Active Synthetic Microrotors: Design Strategies and Applications

ACS Nano, Journal Year: 2023, Volume and Issue: 17(13), P. 11969 - 11993

Published: June 20, 2023

Microrotors are microscopic objects that convert energy stored in the environment into spontaneous rotation, form of spinning along an axis, rolling on a surface, or orbiting circles. Because its distinct dynamics and vertical flows around it, microrotor is potentially useful for applications, including drug delivery, minimally invasive surgery, fluid mixing, sensing. It also as model system to probe collective behaviors among rotating micro-objects. In this review article, we comprehensively recent experimental progress designing, synthesizing, using microrotors. For particular emphasis placed microfluidic biomedicine, behaviors. end, comment how microrotors can be made more biocompatible controllable rotate ways challenges therein. A key feature article introduce three which classify microrotor: nature rotational behavior (spinners, rollers, orbiters), cause rotation (whether chiral symmetry broken by shapes, chemical compositions, way applied), power source powered reactions, electric magnetic fields, light, ultrasound). This will help materials scientists chemists designing micromachines microrotors, engineers finding appropriate specific application, physicists systems.

Language: Английский

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Phase Separation Driven by Active Flows

Physical Review Letters, Journal Year: 2023, Volume and Issue: 130(23)

Published: June 6, 2023

We extend the continuum theories of active nematohydrodynamics to model a two-fluid mixture with separate velocity fields for each fluid component, coupled through viscous drag. The is used study an nematic mixed isotropic fluid. find microphase separation, and argue that this results from interplay between anchoring flows driven by concentration gradients. may be relevant cell sorting formation lipid rafts in membranes.

Language: Английский

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Clustering and ordering in cell assemblies with generic asymmetric aligning interactions

Physical Review Research, Journal Year: 2024, Volume and Issue: 6(2)

Published: April 4, 2024

Collective cell migration plays an essential role in various biological processes, such as development or cancer proliferation. While cell-cell interactions are clearly key determinants of collective -- addition to individual cells self-propulsion the physical mechanisms that control emergence clustering and still poorly understood. In particular, observations have shown binary collisions generally lead anti-alignement polarities separation pairs a process called contact inhibition locomotion (CIL), which is expected disfavor formation large scale clusters with coherent motion. Here, we adopt joint experimental theoretical approach determine dynamics assemblies from elementary pairwise interaction rules. We quantify experimentally show they can be captured by minimal equilibrium-like asymmetric aligning potential reproduces CIL phenomenology. identify its symmetry class, build corresponding active hydrodynamic theory on general grounds destroys ordering, leading instead liquid-like microphase finite size short lived polarity, fully dispersed isotropic phase. Finally, this shows CIL-like cellular systems cluster sizes prevent coarsening long range except singular regime dense confluent systems.

Language: Английский

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Discovering dynamic laws from observations: The case of self-propelled, interacting colloids

Physical review. E, Journal Year: 2024, Volume and Issue: 109(6)

Published: June 26, 2024

Active matter spans a wide range of time and length scales, from groups cells synthetic self-propelled colloids to schools fish flocks birds. The theoretical framework describing these systems has shown tremendous success in finding universal phenomenology. However, further progress is often burdened by the difficulty determining forces controlling dynamics individual elements within each system. Accessing this local information pivotal for understanding physics governing an ensemble active particles creation numerical models capable explaining observed collective phenomena. In work, we present ActiveNet, machine-learning tool consisting graph neural network that uses motion learn two-body their dynamics. We verify our approach using simulations Brownian particles, undergoing underdamped Langevin dynamics, chiral considering different interaction potentials values activity. Interestingly, ActiveNet can equally conservative or nonconservative as well torques. Moreover, proven be useful stochastic contribution forces, enabling estimation diffusion coefficients. Therefore, all coefficients equation Particles are captured. Finally, apply experiments electrophoretic Janus extracting colloids' On one side, have learned force depends on electric field area fraction. other also discovered dependence with leads us propose dominant between screened electrostatic constant scale. believe proposed methodological tool, might open new avenue study modeling experimental suspensions particles.

Language: Английский

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Self-propulsion, flocking and chiral active phases from particles spinning at intermediate Reynolds numbers

Nature Physics, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 8, 2024

Language: Английский

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Anomalous diffusion of active Brownian particles in responsive elastic gels: Nonergodicity, non-Gaussianity, and distributions of trapping times

Physical review. E, Journal Year: 2024, Volume and Issue: 110(4)

Published: Oct. 29, 2024

Understanding actual transport mechanisms of self-propelled particles (SPPs) in complex elastic gels---such as the cell cytoplasm, vitro networks chromatin or F-actin fibers, mucus gels---has far-reaching consequences. Implications beyond biology/biophysics are engineering and medicine, with a particular focus on microrheology targeted drug delivery. Here, we examine via extensive computer simulations dynamics SPPs deformable gellike structures responsive to thermal fluctuations. We treat tracer comparable larger than mesh size gel. observe distinct trapping events active tracers at relatively short times, leading subdiffusion; it is followed by an escape from meshwork-induced traps due flexibility network, resulting superdiffusion. thus find crossovers between different regimes. also pronounced nonergodicity non-Gaussianity intermediate times. The distributions times escaping ``cages'' our quasiperiodic gel often reveal existence two timescales dynamics. At high activity these become comparable. Furthermore, that mean waiting time exhibits power-law dependence (in terms their P\'eclet number). Our results additionally showcase both exponential nonexponential activities. Extensions this setup possible, factors such anisotropy particles, topologies various interactions (also nonlocal nature) be considered.

Language: Английский

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Synthetic electrically driven colloids: A platform for understanding collective behavior in soft matter

Current Opinion in Colloid & Interface Science, Journal Year: 2022, Volume and Issue: 60, P. 101603 - 101603

Published: June 25, 2022

Language: Английский

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Dynamic clustering of passive colloids in dense suspensions of motile bacteria

Physical review. E, Journal Year: 2022, Volume and Issue: 105(5)

Published: May 16, 2022

Mixtures of active and passive particles are predicted to exhibit a variety nonequilibrium phases. Here we report dynamic clustering phase in mixtures colloids motile bacteria. We show that colloidal results from balance between bond breaking due persistent motion stabilization torques align particle velocity tangentially the surface. Furthermore, spans broad regime diffusivity-based motility-induced separation subsumes typical bacterial motility parameters.

Language: Английский

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Aging in thermal active glasses

Physical Review Research, Journal Year: 2022, Volume and Issue: 4(1)

Published: March 28, 2022

It is well established that glassy materials can undergo out-of-equilibrium aging, i.e., their properties gradually change over time. There rapidly growing evidence dense active and living systems also exhibit many features of behavior, but it still largely unknown if how physical aging manifested in such non-Hamiltonian materials. Here we show, by means computer simulations, the dynamics thermal glasses governed a complex interplay different relaxation mechanisms. Notably, identify time-dependent competition between effects, which gives rise to an explicitly age-dependent effective temperature. As consequence, often-invoked mapping system passive one with unique, higher temperature rigorously breaks down upon aging. Moreover, unlike phenomenology, find degree dynamic heterogeneity relatively small remarkably constant age. We attribute these differences activity-enhanced cage breaking, modifies both quantitative qualitative nature process matter.Received 13 May 2021Revised 8 July 2021Accepted 6 February 2022DOI:https://doi.org/10.1103/PhysRevResearch.4.L012038Published American Physical Society under terms Creative Commons Attribution 4.0 International license. Further distribution this work must maintain attribution author(s) published article's title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasAgingBrownian motionDiffusionNonequilibrium statistical mechanicsPhysical SystemsActive matterGlassy systemsStatistical Physics

Language: Английский

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