Effective Langevin equations for a polar tracer in an active bath
| dc.contributor.author | Knežević, Miloš | |
| dc.contributor.author | Stark, Holger | |
| dc.date.accessioned | 2022-02-17T15:13:33Z | |
| dc.date.available | 2022-02-17T15:13:33Z | |
| dc.date.issued | 2020-11-23 | |
| dc.date.updated | 2022-02-11T17:25:47Z | |
| dc.description.abstract | We study the motion of a polar tracer, having a concave surface, immersed in a two-dimensional suspension of active particles. Using Brownian dynamics simulations, we measure the distributions and auto-correlation functions of force and torque exerted by active particles on the tracer. The tracer experiences a finite average force along its polar axis, while all the correlation functions show exponential decay in time. Using these insights we construct the full coarse-grained Langevin description for tracer position and orientation, where the active particles are subsumed into an effective self-propulsion force and exponentially correlated noise for both translations and rotations. The ensuing mesoscopic dynamics can be described in terms of five dimensionless parameters. We perform a thorough parameter study of the mean squared displacement, which illustrates how the different parameters influence the tracer dynamics, which crosses over from a ballistic to diffusive motion. We also demonstrate that the distribution of tracer displacements evolves from a non-Gaussian shape at early stages to a Gaussian behavior for sufficiently long times. Finally, for a given set of microscopic parameters, we establish a procedure to estimate the matching parameters of our effective model, and show that the resulting dynamics is in a very good quantitative agreement with the one obtained in Brownian dynamics simulations. | en |
| dc.description.sponsorship | DFG, 163436311, SFB 910: Kontrolle selbstorganisierender nichtlinearer Systeme: Theoretische Methoden und Anwendungskonzepte | en |
| dc.identifier.eissn | 1367-2630 | |
| dc.identifier.uri | https://depositonce.tu-berlin.de/handle/11303/16438 | |
| dc.identifier.uri | http://dx.doi.org/10.14279/depositonce-15214 | |
| dc.language.iso | en | en |
| dc.rights.uri | https://creativecommons.org/licenses/by/4.0/ | en |
| dc.subject.ddc | 530 Physik | de |
| dc.subject.other | Langevin equations | en |
| dc.subject.other | tracer | en |
| dc.subject.other | active bath | en |
| dc.title | Effective Langevin equations for a polar tracer in an active bath | en |
| dc.type | Article | en |
| dc.type.version | publishedVersion | en |
| dcterms.bibliographicCitation.articlenumber | 113025 | en |
| dcterms.bibliographicCitation.doi | 10.1088/1367-2630/abc91e | en |
| dcterms.bibliographicCitation.issue | 11 | en |
| dcterms.bibliographicCitation.journaltitle | New Journal of Physics | en |
| dcterms.bibliographicCitation.originalpublishername | IOP | en |
| dcterms.bibliographicCitation.originalpublisherplace | Bristol | en |
| dcterms.bibliographicCitation.volume | 22 | en |
| tub.accessrights.dnb | free | en |
| tub.affiliation | Fak. 2 Mathematik und Naturwissenschaften::Inst. Theoretische Physik::FG Statistische Physik weicher Materie und biologischer Systeme | de |
| tub.affiliation.faculty | Fak. 2 Mathematik und Naturwissenschaften | de |
| tub.affiliation.group | FG Statistische Physik weicher Materie und biologischer Systeme | de |
| tub.affiliation.institute | Inst. Theoretische Physik | de |
| tub.publisher.universityorinstitution | Technische Universität Berlin | en |