From the University of Texas at Austin:
In a breakthrough for nanotechnology, engineers at The University of Texas at Austin have developed the first method for selecting and switching the mechanical motion of nanomotors among multiple modes with simple visible light as the stimulus.
The capability of mechanical reconfiguration could lead to a new class of controllable nanoelectromechanical and nanorobotic devices for a variety of fields including drug delivery, optical sensing, communication, molecule release, detection, nanoparticle separation and microfluidic automation.
The finding, made by Donglei (Emma) Fan, associate professor at the Cockrell School of Engineering's Department of Mechanical Engineering, and Ph.D. candidate Zexi Liang, demonstrates how, depending on the intensity, light can instantly increase, stop and even reverse the rotation orientation of silicon nanomotors in an electric field. This effect and the underlying physical principles have been unveiled for the first time. It switches mechanical motion of rotary nanomotors among various modes instantaneously and effectively.
Journal Reference:
Zexi Liang, Donglei Fan. Visible light–gated reconfigurable rotary actuation of electric nanomotors. Science Advances, 2018; 4 (9): eaau0981 DOI: 10.1126/sciadv.aau0981
(Score: 3, Interesting) by crafoo on Saturday September 22 2018, @03:11PM
This is some real sci-fi stuff.
Here is a link of a diagram of the setup from the linked paper/article:
http://advances.sciencemag.org/content/advances/4/9/eaau0981/F1.large.jpg?width=800&height=600&carousel=1 [sciencemag.org]
The underlying principle they identified (from the abstract):
"[...]which can be attributed to the optically tunable polarization of Si nanowires in an aqueous suspension and an external E-field."
It's a pretty cool attribute and an interesting paper. I think it gets interesting when you consider millions of these things, which could be controlled in zones to create complex fluid flows.