Viscoelastic flows in simple liquids generated by vibrating nanostructures.
Newtonian fluid mechanics, in which the shear stress is proportional to the strain rate, is synonymous with the flow of simple liquids such as water. We report the measurement and theoretical verification of non-Newtonian, viscoelastic flow phenomena produced by the high-frequency (20 GHz) vibration of gold nanoparticles immersed in water-glycerol mixtures. The observed viscoelasticity is not due to molecular confinement, but is a bulk continuum effect arising from the short time scale of vibration. This represents the first direct mechanical measurement of the intrinsic viscoelastic properties of simple bulk liquids, and opens a new paradigm for understanding extremely high frequency fluid mechanics, nanoscale sensing technologies, and biophysical processes.
Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Matthew
M
Pelton
Department of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia.
Debadi
D
Chakraborty
James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
Edward
E
Malachosky
James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
Philippe
P
Guyot-Sionnest
Department of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia and Kavli Nanoscience Institute and Department of Physics, California Institute of Technology, Pasadena, California 91125, USA.
John E
JE
Sader