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Active particles in complex and crowded environments

Clemens Bechinger, Roberto Di Leonardo, Hartmut Löwen, Charles Reichhardt, Giorgio Volpe, and Giovanni Volpe*

Clemens Bechinger

  • Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany and Max-Planck-Institut für Intelligente Systeme, Heisenbergstraße 3, 70569 Stuttgart, Germany

Roberto Di Leonardo

  • Dipartimento di Fisica, Università “Sapienza,” I-00185, Roma, Italy and NANOTEC-CNR Institute of Nanotechnology, Soft and Living Matter Laboratory, I-00185 Roma, Italy

Hartmut Löwen

  • Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf, Germany

Charles Reichhardt

  • Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

Giorgio Volpe

  • Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom

Giovanni Volpe*

  • Department of Physics, University of Gothenburg, SE-41296 Gothenburg, Sweden and Soft Matter Lab, Department of Physics, and UNAM—National Nanotechnology Research Center, Bilkent University, Ankara 06800, Turkey

  • *giovanni.volpe@physics.gu.se
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Rev. Mod. Phys. 88, 045006 – Published 23 November, 2016

DOI: https://doi.org/10.1103/RevModPhys.88.045006

Abstract

Differently from passive Brownian particles, active particles, also known as self-propelled Brownian particles or microswimmers and nanoswimmers, are capable of taking up energy from their environment and converting it into directed motion. Because of this constant flow of energy, their behavior can be explained and understood only within the framework of nonequilibrium physics. In the biological realm, many cells perform directed motion, for example, as a way to browse for nutrients or to avoid toxins. Inspired by these motile microorganisms, researchers have been developing artificial particles that feature similar swimming behaviors based on different mechanisms. These man-made micromachines and nanomachines hold a great potential as autonomous agents for health care, sustainability, and security applications. With a focus on the basic physical features of the interactions of self-propelled Brownian particles with a crowded and complex environment, this comprehensive review will provide a guided tour through its basic principles, the development of artificial self-propelling microparticles and nanoparticles, and their application to the study of nonequilibrium phenomena, as well as the open challenges that the field is currently facing.

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Rev. Mod. Phys. 88, 045006– Published 23 November, 2016
  • Received 30 January 2016

© 2016 American Physical Society

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