Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Switching light on and off -- with just a few photons at a time

Gaeta Group
Rubidium atoms will absorb photons only if two photons of specific wavelengths arrive at the same time. This allows one stream of photons to turn another on or off.
Gaeta Group

Rubidium atoms will absorb photons only if two photons of specific wavelengths arrive at the same time. This allows one stream of photons to turn another on or off.

Abstract:
Cornell researchers have demonstrated that the passage of a light beam through an optical fiber can be controlled by just a few photons of another light beam.

Switching light on and off -- with just a few photons at a time

Ithaca, NY | Posted on November 9th, 2011

Such all-optical control is the idea behind photonics, where beams of light replace electric currents in circuits, yielding higher speed and lower power consumption. Just as a transistor can switch an electric current on or off, photonic circuits need a way for one light beam to switch another. One of the holy grails is single-photon switching, where just one photon controls the passage of another.

Researchers in the Quantum and Nonlinear Optics group of Alexander Gaeta, professor of applied and engineering physics, have come close to that goal. They report their new approach in the Nov. 4 issue of the journal Physical Review Letters.

Light consists of small packets of energy called photons. Under the right conditions, a photon can be absorbed by an atom. Gaeta's group exploited the unusual property of the element rubidium, which can absorb photons only if two photons of certain wavelengths arrive at the same time. They filled a hollow-core optical fiber with rubidium vapor and fired a continuous infrared light signal at a wavelength of 776 nanometers (nm) in one end and an intermittent "control" signal at 780.2 nm in the other.

In the narrow tube, light interacts strongly with the rubidium atoms. When the control beam is on, rubidium atoms absorb both wavelengths, and the signal is cut off; when the control is off the signal passes through.

The effect is observed with less than 20 control photons at timescales as fast as five-billionths of a second, allowing modulation at frequencies up to 50MHz, the researchers said, referring to the rate of transmission of on and off pulses of light representing digital ones and zeroes in fiber-optic communication. The technique also may have applications in quantum computing, where single photons can act as "qubits," the quantum equivalent of ones and zeroes.

The research was funded by the National Science Foundation and the Defense Advanced Research Projects Agency.

==

Graduate student Vivek Venkataraman is a writer intern for the Cornell Chronicle.

####

For more information, please click here

Contacts:
Media Contact:
Blaine Friedlander
(607) 254-8093


Cornell Chronicle:
Bill Steele
(607) 255-7164


Vivek Venkataraman

Copyright © Cornell University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

Iranian Scientists Determine Grain Size, Minimize Time of Nanocomposite Synthesis September 29th, 2014

Nanoparticles Used to Improve Quality of Bone Cement September 29th, 2014

Optical Computing

'Pixel' engineered electronics have growth potential: Rice, Oak Ridge, Vanderbilt, Penn scientists lead creation of atom-scale semiconducting composites September 29th, 2014

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 2014

Atomically thin material opens door for integrated nanophotonic circuits September 4th, 2014

Discoveries

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

Iranian Scientists Determine Grain Size, Minimize Time of Nanocomposite Synthesis September 29th, 2014

Nanoparticles Used to Improve Quality of Bone Cement September 29th, 2014

Announcements

Chemical interactions between silver nanoparticles and thiols: A comparison of mercaptohexanol again September 30th, 2014

A Heartbeat Away? Hybrid "Patch" Could Replace Transplants: TAU researcher harnesses gold nanoparticles to engineer novel biocompatible cardiac patch September 30th, 2014

Iranian Scientists Determine Grain Size, Minimize Time of Nanocomposite Synthesis September 29th, 2014

Nanoparticles Used to Improve Quality of Bone Cement September 29th, 2014

Photonics/Optics/Lasers

'Pixel' engineered electronics have growth potential: Rice, Oak Ridge, Vanderbilt, Penn scientists lead creation of atom-scale semiconducting composites September 29th, 2014

Southampton scientists grow a new challenger to graphene September 23rd, 2014

Engineers show light can play seesaw at the nanoscale: Discovery is another step toward faster and more energy-efficient optical devices for computation and communication September 22nd, 2014

Twisted graphene chills out: When two sheets of graphene are stacked in a special way, it is possible to cool down the graphene with a laser instead of heating it up, University of Manchester researchers have shown September 22nd, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE