September 7, 2012
Water Droplets Could Be Used For A New Way Of Computing
Lee Rannals for redOrbit.com — Your Universe Online
[ Watch the Video: Superhydrophobic Droplet Logic: Flip-Flop Memory ]
Aalto University researchers are using water droplets as bits of digital information to create a new way of computing.
The new concept was made possible through the discovery that upon collision with each other on a highly water-repellant surface, two water droplets rebound like billiard balls.
This method enables the surface to be so water-repellant that water droplets roll off when the surface is tilted slightly.
Superhydrophobic tracks that were developed during the previous study were used to guide droplets along designed paths.
The team used the tracks to demonstrate that water droplets could be turned into technology called "superhydrophobic droplet logic."
Devices for elementary Boolean logic operations could be demonstrated through this concept. Also, a memory device was built where water droplets act as bits of digital information.
When the water droplets are loaded with reactive chemical cargo, the onset of a chemical reaction could be controlled by droplet collisions.
When combining collision-controlled chemical reactions with droplet logic operations, it enables programmable chemical reactions where single droplets serve simultaneously as miniature reactors and bits for computing.
"It is fascinating to observe a new physical phenomenon for such everyday objects," Robin Ras, an Academy Research Fellow in the Molecular Materials research group, said in a statement.
Henrikki Mertaniemi, who discovered the rebounding droplet collisions two years ago during a summer student project in the research group of Ras and Academy Professor Olli Ikkala, said that he was surprised that these collisions had never been reported before.
"I was surprised that such rebounding collisions between two droplets were never reported before, as it indeed is an easily accessible phenomenon: I conducted some of the early experiments on water-repellent plant leaves from my mother´s garden, explains a member of the research group," Mertaniemi said in the statement.
The team believes that the present results will enable technology based on superhydrophobic droplet logic. Applications for the new concept could include autonomous simple logic devices that do not require electricity, and programmable biochemical analysis devices.