• Featured in Physics
  • Editors' Suggestion

Relating Rheotaxis and Hydrodynamic Actuation using Asymmetric Gold-Platinum Phoretic Rods

Quentin Brosseau, Florencio Balboa Usabiaga, Enkeleida Lushi, Yang Wu, Leif Ristroph, Jun Zhang, Michael Ward, and Michael J. Shelley
Phys. Rev. Lett. 123, 178004 – Published 25 October 2019
Physics logo See Focus story: Asymmetry Helps Tiny Rods Swim Upstream
PDFHTMLExport Citation

Abstract

We explore the behavior of micron-scale autophoretic Janus (Au/Pt) rods, having various Au/Pt length ratios, swimming near a wall in an imposed background flow. We find that their ability to robustly orient and move upstream, i.e., to rheotax, depends strongly on the Au/Pt ratio, which is easily tunable in synthesis. Numerical simulations of swimming rods actuated by a surface slip show a similar rheotactic tunability when varying the location of the surface slip versus surface drag. The slip location determines whether swimmers are pushers (rear actuated), pullers (front actuated), or in between. Our simulations and modeling show that pullers rheotax most robustly due to their larger tilt angle to the wall, which makes them responsive to flow gradients. Thus, rheotactic response infers the nature of difficult to measure flow fields of an active particle, establishes its dependence on swimmer type, and shows how Janus rods can be tuned for flow responsiveness.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 13 June 2019
  • Revised 20 August 2019

DOI:https://doi.org/10.1103/PhysRevLett.123.178004

© 2019 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied PhysicsFluid DynamicsPhysics of Living Systems

Focus

Key Image

Asymmetry Helps Tiny Rods Swim Upstream

Published 25 October 2019

Changing the length ratio of the two segments of a microswimmer affects its ability to automatically swim against the current.

See more in Physics

Authors & Affiliations

Quentin Brosseau1, Florencio Balboa Usabiaga2, Enkeleida Lushi3, Yang Wu4, Leif Ristroph1, Jun Zhang1,5,6, Michael Ward4, and Michael J. Shelley1,2

  • 1Courant Institute, New York University, New York, New York 10012, USA
  • 2Center for Computational Biology, Flatiron Institute, New York, New York 10010, USA
  • 3Department of Mathematics, New Jersey Institute of Technology, Newark, New Jersey 07102, USA
  • 4Department of Chemistry, New York University, New York, New York 10012, USA
  • 5Department of Physics, New York University, New York, New York 10003, USA
  • 6New York University-East China Normal University Institute of Physics, New York University Shanghai, Shanghai 200062, China

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 123, Iss. 17 — 25 October 2019

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×