A Landau-Squire Nanojet

Nadanai Laohakunakorn; Benjamin Gollnick; Fernando Moreno-Herrero; Dirk G. A. L. Aarts; Roel P. A. Dullens; Sandip Ghosal; Ulrich F. Keyser

doi:10.1021/nl402350a

arXiv · 1311.2640

A Landau-Squire Nanojet

Nadanai Laohakunakorn·Benjamin Gollnick·Fernando Moreno-Herrero·Dirk G. A. L. Aarts·Roel P. A. Dullens·Sandip Ghosal·Ulrich F. Keyser

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Abstract

Fluid jets are found in nature at all length scales, from microscopic to cosmological. Here we report on an electroosmotically driven jet from a single glass nanopore about 75 nm in radius with a maximum flow rate ~15 pL/s. A novel anemometry technique allows us to map out the vorticity and velocity fields that show excellent agreement with the classical Landau-Squire solution of the Navier Stokes equations for a point jet. We observe a phenomenon that we call flow rectification: an asymmetry in the flow rate with respect to voltage reversal. Such a nanojet could potentially find applications in micromanipulation, nanopatterning, and as a diode in microfluidic circuits.

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Nadanai Laohakunakorn, Benjamin Gollnick, Fernando Moreno-Herrero, Dirk G. A. L. Aarts, Roel P. A. Dullens, Sandip Ghosal, Ulrich F. Keyser. 2013-11-11. A Landau-Squire Nanojet. https://doi.org/10.1021/nl402350a

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