Physicists at UC Berkeley, build world's smallest electric motor

from Physics News Update
The smallest electric motor in the world, devised by physicists at UC Berkeley, is based on the shuttling of atoms between two metal droplets---one large and one small---residing on the back of a carbon nanotube. An electric current transmitted through the nanotube causes atoms to move from the big to the small droplet. In effect, potential energy is being stored in the smaller droplet in the form of surface tension.

Eventually the smaller drop grows so much that the two droplets touch. Then the accumulated energy is suddenly discharged as the larger droplet reabsorbs its atoms through the newly created hydrodynamic channel. This device constitutes a "relaxation oscillator" with an adjustable operating frequency. If the oscillator is attached to a mechanical linkage, it acts as a motor and can be used to move a MEMS device in inchworm fashion. Movie

The peak pulsed power is 20 microwatts. Considering that the device is less than 200 nm on a side, the power density works out to about 100 million times that of the 225 hp V6 engine in a Toyota Camry. Chris Regan ([email protected]), a member of Alex Zettl's group at Berkeley, reported these and related results at the recent APS meeting in Los Angeles and in the 21 March 2005 issue of Applied Physics Letters.

Very powerfull for such a small device

the Zettl Research Group is an experimental solid state physics group who are currently investigating electronic, magnetic and mechanical properties of nanoscale materials.

Could this have any possible implications to our current energy crisis? Is it feasible to use this type of technology on a wide scale? Either way these guys are doing some very interesting and cutting-edge physics

[edit on 12-5-2005 by Rren]

Very powerfull for such a small device

Darned right it is. That's amazing!

Could this have any possible implications to our current energy crisis? Is it feasible to use this type of technology on a wide scale? Either way these guys are doing some very interesting and cutting-edge physics

I didn't see a lot of details on the link you provided, but fortunately I took a nanotechnology course last semester, so I have a bit of a grasp of this kind of stuff. Due to the extreme difficulty in manufacturing anything nanoscale, I don't see this as being feasible on a wide scale, and therefore I don't see it as helping the energy crisis, at least at the present time. One thing that nanotech researchers want to do is produce self-assembling nanodevices, which has obvious advantages. There's been a small amount of progress in self-assembly, but nothing anywhere near the level to be useful for something like this.

I find it fascinating that this device is able to keep working, though. I would have thought that after the smaller drop grows to be the same size as the bigger drop and they touch, that it would quit working, but the one drop absorbs the other and then the process starts over.

Due to the coolness of this idea I am giving you a vote for way above (I'm a sucker for anything nano, lol)

thanks for the vote

researchers at Rutgers' are also working on a nano-motor:

from Spacedaily.com
Three engineering departments at Rutgers, The State University of New Jersey – mechanical and aerospace, biomedical, and chemical and biochemical – are teaming up to create a prototype of an ultra-tiny motor small enough to be part of a system that could eventually travel patients' bloodstreams to help repair damaged cells, organs and DNA.
A prototype of the "Viral Protein Nano Motor" is expected to be unveiled in 2007, with research and development funded by a four-year $1,050,017 grant from the National Science Foundation and its Nanoscale Science and Engineering program.

Yeah no "energy crisis" applications as of yet, that I can see. However this research is still very much in its' infancy. It realy is amazing what they are doing with nano-tech

Link to Rutgers' site

Providing a power source for nano machines is very difficult due to the problems of attaching to external electrical or mechanical contacts. Researchers at Harvard University and the Weizmann Science Institute report that laser light may be the fuel of the future, and its very clean too.

from UPI.com
Kral and Sadeghpour used lasers to transfer the angular or sideways momentum of infrared light-bearing photons to carbon nanotubes. The tubes, thousands of times thinner than a human hair and with walls only one atom thick, then rotated like whirring turbines.

Scientists at the Department of Energy's Oak Ridge National Laboratory designed the first laser-driven nanomotor -- a cylindrical carbon tube surrounded by a carbon sleeve. In theory, applying an oscillating laser field would make the tube rotate enough to power a tiny motor, chemists Donald Noid, Bobby Sumpter and computer scientist Robert Tuzun explained in a groundbreaking 1995 paper.

"When we started to consider nanotechnology, we thought that a method would be required to use some form of energy that could create mechanical motion," Oak Ridge National Laboratory senior scientist Donald Noid told UPI. "The most simple approach we could envision was that of rotation of nanotubes with lasers."

The Oak Ridge team only simulated a laser-powered nanomotor, however. The Harvard-Weizmann team said they have the blueprint for a working prototype.