title: Active Brownian particles and run-and-tumble particles separate inside a maze.
abstract: A diverse range of natural and artificial self-propelled particles are known and are used nowadays. Among them, active Brownian particles (ABPs) and run-and-tumble particles (RTPs) are two important classes. We numerically study non-interacting ABPs and RTPs strongly confined to different maze geometries in two dimensions. We demonstrate that by means of geometrical confinement alone, ABPs are separable from RTPs. By investigating Matryoshka-like mazes with nested shells, we show that a circular maze has the best filtration efficiency. Results on the mean first-passage time reveal that ABPs escape faster from the center of the maze, while RTPs reach the center from the rim more easily. According to our simulations and a rate theory, which we developed, ABPs in steady state accumulate in the outermost region of the Matryoshka-like mazes, while RTPs occupy all locations within the maze with nearly equal probability. These results suggest a novel technique for separating different types of self-propelled particles by designing appropriate confining geometries without using chemical or biological agents.
authors.affiliation: Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran, Iran.|Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
authors.forename: Maryam
authors.initials: M
authors.lastname: Khatami
authors.affiliation: Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Wolff
authors.affiliation: Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Pohl
authors.affiliation: Department of Physics, Sharif University of Technology, P.O. Box 11155-9161, Tehran, Iran.|School of Nano-Science, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Ejtehadi
authors.affiliation: Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Stark
mesh_terms: D003198:Computer Simulation; D008962:Models, Theoretical; D011336:Probability; D013997:Time Factors