Featured Research

from universities, journals, and other organizations

Setting Micro Gears In Motion

Date:
February 19, 2002
Source:
University Of California - Riverside
Summary:
The movement of gears and motors in micromachines just got easier because of the lateral Casimir force. This force acts tangential to two surfaces, resulting in a horizontal sliding motion of one surface against the other.

The movement of gears and motors in micromachines just got easier because of the lateral Casimir force. This force acts tangential to two surfaces, resulting in a horizontal sliding motion of one surface against the other.

The University of California, Riverside's Umar Mohideen, associate professor of physics, has performed the first demonstration of the lateral Casimir force (a shape-dependent Casimir force) in his laboratory. His findings will be published in an upcoming issue of Physical Review Letters. The Casimir force has its origins in virtual particles that exist in empty space.

"The virtual particles are also called quantum fluctuations," Mohideen said. "They are predicted for all the fundamental forces in physics." Mohideen's experiment deals with the electromagnetic force and relies on virtual photons or particles of light, which are intermediaries for the electromagnetic force.

The Dutch physicist Hendrik Casimir realized that the properties of the virtual particles could be controlled by introducing boundaries. He predicted that if two parallel metallic plates are brought very close to each other then the Casimir force, named after him, comes into play.

Mohideen explained that the force arises because the number of virtual photons between the plates is smaller than the number of photons outside the plates. "The photons outside bounce off the plates," he said. "In doing so, they push the plates together, effectively leading to an attractive force between the plates. This is the normal Casimir force, where normal means perpendicular. If the shape of the plates is changed, however, you get different forces."

Indeed, the Casimir force can also manifest itself as a repulsive force. While the force is attractive in nature for two parallel plates, for two hemispherical shells, whose circular rims can be placed against each other to form one sphere, the force is repulsive and tends to break the sphere apart. The lateral Casimir force, which Mohideen's laboratory has demonstrated and which MIT physicist Meharan Kardar predicted in 1997, is another such shape-dependent Casimir force. Its result: a horizontal sliding motion between two surfaces.

"The lateral Casimir force has wide applications," Mohideen said. "One can envision a device fabricated with two corrugated surfaces allowing for a sliding motion between the two surfaces. The normal Casimir force would move the membrane up and down in the vertical plane, while the lateral Casimir force would slide it back and forth. Thus, on a silicon chip you can have vertical and sliding motions of a micro device."

The Casimir force would have vast implications for micromachines. "The effect of the force on the individual parts of the machines would need to be considered," said Mohideen. "This would be important in the silicon chip industry."


Story Source:

The above story is based on materials provided by University Of California - Riverside. Note: Materials may be edited for content and length.


Cite This Page:

University Of California - Riverside. "Setting Micro Gears In Motion." ScienceDaily. ScienceDaily, 19 February 2002. <www.sciencedaily.com/releases/2002/02/020219080529.htm>.
University Of California - Riverside. (2002, February 19). Setting Micro Gears In Motion. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2002/02/020219080529.htm
University Of California - Riverside. "Setting Micro Gears In Motion." ScienceDaily. www.sciencedaily.com/releases/2002/02/020219080529.htm (accessed September 30, 2014).

Share This



More Matter & Energy News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Argentina's Tax Evaders Detected, Hunted Down by Drones

Argentina's Tax Evaders Detected, Hunted Down by Drones

AFP (Sep. 30, 2014) Argentina doesn't only have Lionel Messi the footballer, it has now also acquired "Mesi" the drone system which monitors undeclared mansions, swimming pools and soy fields to curb tax evasion in the country. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Do Video Games Trump Brain Training For Cognitive Boosts?

Do Video Games Trump Brain Training For Cognitive Boosts?

Newsy (Sep. 29, 2014) More and more studies are showing positive benefits to playing video games, but the jury is still out on brain training programs. Video provided by Newsy
Powered by NewsLook.com
CERN Celebrates 60 Years of Science

CERN Celebrates 60 Years of Science

Reuters - Business Video Online (Sep. 29, 2014) CERN, the European Organisation for Nuclear Research, celebrates 60 years of bringing nations together through science. As Joanna Partridge reports from inside the famous science centre it's also planning to turn the Large Hadron Collider particle accelerator back on after an upgrade. Video provided by Reuters
Powered by NewsLook.com
This 'Invisibility Cloak' Is Simpler Than Most

This 'Invisibility Cloak' Is Simpler Than Most

Newsy (Sep. 28, 2014) Researchers from the University of Rochester have created a type of invisibility cloak with simple focal lenses. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins