Featured Research

from universities, journals, and other organizations

'Repulsive' Side To Light Force Could Control Nanodevices

Date:
July 13, 2009
Source:
Yale University
Summary:
Researchers have discovered a "repulsive" light force that can be used to control components on silicon microchips, meaning future nanodevices could be controlled by light rather than electricity.

Tang's team show how interacting lightwaves can be used to control devices on a silicon chip.
Credit: Photo: Hong Tang/Yale University

A team of Yale University researchers has discovered a "repulsive" light force that can be used to control components on silicon microchips, meaning future nanodevices could be controlled by light rather than electricity.

The team previously discovered an "attractive" force of light and showed how it could be manipulated to move components in semiconducting micro- and nano-electrical systems—tiny mechanical switches on a chip. The scientists have now uncovered a complementary repulsive force. Researchers had theorized the existence of both the attractive and repulsive forces since 2005, but the latter had remained unproven until now. The team, led by Hong Tang, assistant professor at Yale's School of Engineering & Applied Science, reports its findings in the July 13 edition of Nature Photonics's advanced online publication.

"This completes the picture," Tang said. "We've shown that this is indeed a bipolar light force with both an attractive and repulsive component."

The attractive and repulsive light forces Tang's team discovered are separate from the force created by light's radiation pressure, which pushes against an object as light shines on it. Instead, they push out or pull in sideways from the direction the light travels.

Previously, the engineers used the attractive force they discovered to move components on the silicon chip in one direction, such as pulling on a nanoscale switch to open it, but were unable to push it in the opposite direction.

Using both forces means they can now have complete control and can manipulate components in both directions. "We've demonstrated that these are tunable forces we can engineer," Tang said.

In order to create the repulsive force, or the "push," on a silicon chip, the team split a beam of infrared light into two separate beams and forced each one to travel a different length of silicon nanowire, called a waveguide. As a result, the two light beams became out of phase with one another, creating a repulsive force with an intensity that can be controlled—the more out of phase the two light beams, the stronger the force.

"We can control how the light beams interact," said Mo Li, a postdoctoral associate in electrical engineering at Yale and lead author of the paper. "This is not possible in free space—it is only possible when light is confined in the nanoscale waveguides that are placed so close to each other on the chip."

"The light force is intriguing because it works in the opposite way as charged objects," said Wolfram Pernice, another postdoctoral fellow in Tang's group. "Opposite charges attract each other, whereas out-of-phase light beams repel each other in this case."

These light forces may one day control telecommunications devices that would require far less power but would be much faster than today's conventional counterparts, Tang said. An added benefit of using light rather than electricity is that it can be routed through a circuit with almost no interference in signal, and it eliminates the need to lay down large numbers of electrical wires.

Funding for the project includes a seed grant from the U.S. Defense Advanced Research Projects Agency and a Young Faculty Award from the National Science Foundation.

Citation: DOI: 10.1038/NPHOTON.2009.116


Story Source:

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


Cite This Page:

Yale University. "'Repulsive' Side To Light Force Could Control Nanodevices." ScienceDaily. ScienceDaily, 13 July 2009. <www.sciencedaily.com/releases/2009/07/090713131556.htm>.
Yale University. (2009, July 13). 'Repulsive' Side To Light Force Could Control Nanodevices. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2009/07/090713131556.htm
Yale University. "'Repulsive' Side To Light Force Could Control Nanodevices." ScienceDaily. www.sciencedaily.com/releases/2009/07/090713131556.htm (accessed July 29, 2014).

Share This




More Matter & Energy News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Baluchistan Mining Eyes an Uncertain Future

Baluchistan Mining Eyes an Uncertain Future

AFP (July 29, 2014) Coal mining is one of the major industries in Baluchistan but a lack of infrastructure and frequent accidents mean that the area has yet to hit its potential. Duration: 01:58 Video provided by AFP
Powered by NewsLook.com
Easier Nuclear Construction Promises Fall Short

Easier Nuclear Construction Promises Fall Short

AP (July 29, 2014) The U.S. nuclear industry started building its first new plants using prefabricated Lego-like blocks meant to save time and prevent the cost overruns that crippled the sector decades ago. So far, it's not working. (July 29) Video provided by AP
Powered by NewsLook.com
Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Newsy (July 28, 2014) Stanford University published its findings for a "pure" lithium ion battery that could have our everyday devices and electric cars running longer. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
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:
from the past week

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