Featured Research

from universities, journals, and other organizations

In Tiny Supercooled Clouds, Physicists Exchange Light And Matter

Date:
February 8, 2007
Source:
Harvard University
Summary:
Physicists have for the first time stopped and extinguished a light pulse in one part of space and then revived it in a completely separate location. They accomplished this feat by completely converting the light pulse into matter that travels between the two locations and is subsequently changed back to light. Matter, unlike light, can easily be manipulated, and the experiments provide a powerful means to control optical information.

Lene Hau explains how she stops light in one place then retrieves and speeds it up in a completely separate place. (Staff photo Justin Ide/Harvard News Office)

Physicists have for the first time stopped and extinguished a light pulse in one part of space and then revived it in a completely separate location. They accomplished this feat by completely converting the light pulse into matter that travels between the two locations and is subsequently changed back to light.

Matter, unlike light, can easily be manipulated, and the experiments provide a powerful means to control optical information. The findings, published this week by Harvard University researchers in the journal Nature, could present an entirely new way for scientists and engineers to manipulate the light pulses used in fiber-optic communications, the technology at the heart of our highly networked society.

"We demonstrate that we can stop a light pulse in a supercooled sodium cloud, store the data contained within it, and totally extinguish it, only to reincarnate the pulse in another cloud two-tenths of a millimeter away," says Lene Vestergaard Hau, Mallinckrodt Professor of Physics and of Applied Physics in Harvard's Faculty of Arts and Sciences and School of Engineering and Applied Sciences.

Hau and her co-authors, Naomi S. Ginsberg and Sean R. Garner, found that the light pulse can be revived, and its information transferred between the two clouds of sodium atoms, by converting the original optical pulse into a traveling matter wave which is an exact matter copy of the original pulse, traveling at a leisurely 200 meters per hour. The matter pulse is readily converted back into light when it enters the second of the supercooled clouds -- known as Bose-Einstein condensates -- and is illuminated with a control laser.

"The Bose-Einstein condensates are very important to this work because within these clouds atoms become phase-locked, losing their individuality and independence," Hau says. "The lock-step nature of atoms in a Bose-Einstein condensate makes it possible for the information in the initial light pulse to be replicated exactly within the second cloud of sodium atoms, where the atoms collaborate to revive the light pulse."

Within a Bose-Einstein condensate -- a cloud of sodium atoms cooled to just billionths of a degree above absolute zero -- a light pulse is spatially compressed by a factor of 50 million. The light drives a controllable number of the condensate's roughly 1.8 million sodium atoms to enter into quantum superposition states with a lower-energy component that stays put and a higher-energy component that travels between the two Bose-Einstein condensates. The amplitude and phase of the light pulse stopped and extinguished in the first cloud are imprinted in this traveling component and transferred to the second cloud, where the recaptured information can recreate the original light pulse.

The period of time when the light pulse becomes matter, and the matter pulse is isolated in space between the condensate clouds, could offer scientists and engineers a tantalizing new window for controlling and manipulating optical information; researchers cannot now readily control optical information during its journey, except to amplify the signal to avoid fading. The new work by Hau and her colleagues marks the first successful manipulation of coherent optical information.

"This work could provide a missing link in the control of optical information," Hau says. "While the matter is traveling between the two Bose-Einstein condensates, we can trap it, potentially for minutes, and reshape it -- change it -- in whatever way we want. This novel form of quantum control could also have applications in the developing fields of quantum information processing and quantum cryptography."

Ginsberg, Garner, and Hau's work was supported by the Air Force Office of Sponsored Research, the National Science Foundation, and the National Aeronautics and Space Administration.


Story Source:

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


Cite This Page:

Harvard University. "In Tiny Supercooled Clouds, Physicists Exchange Light And Matter." ScienceDaily. ScienceDaily, 8 February 2007. <www.sciencedaily.com/releases/2007/02/070207171935.htm>.
Harvard University. (2007, February 8). In Tiny Supercooled Clouds, Physicists Exchange Light And Matter. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2007/02/070207171935.htm
Harvard University. "In Tiny Supercooled Clouds, Physicists Exchange Light And Matter." ScienceDaily. www.sciencedaily.com/releases/2007/02/070207171935.htm (accessed July 30, 2014).

Share This




More Matter & Energy News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Britain Testing Driverless Cars on Roadways

Britain Testing Driverless Cars on Roadways

AP (July 30, 2014) British officials said on Wednesday that driverless cars will be tested on roads in as many as three cities in a trial program set to begin in January. Officials said the tests will last up to three years. (July 30) Video provided by AP
Powered by NewsLook.com
China's Drone King Says the Revolution Depends on Regulators

China's Drone King Says the Revolution Depends on Regulators

Reuters - Business Video Online (July 30, 2014) Comparing his current crop of drones to early personal computers, DJI founder Frank Wang says the industry is poised for a growth surge - assuming regulators in more markets clear it for takeoff. Jon Gordon reports. Video provided by Reuters
Powered by NewsLook.com
3Doodler Bring 3-D Printing to Your Hand

3Doodler Bring 3-D Printing to Your Hand

AP (July 30, 2014) 3-D printing is a cool technology, but it's not exactly a hands-on way to make things. Enter the 3Doodler: the pen that turns you into the 3-D printer. AP technology writer Peter Svensson takes a closer look. (July 30) Video provided by AP
Powered by NewsLook.com
Climate Change Could Cost Billions, According To White House

Climate Change Could Cost Billions, According To White House

Newsy (July 29, 2014) A report from the White House warns not curbing greenhouse gas emissions could cost the U.S. billions. 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:
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