Super slow light may help speed optical communications

October 14, 2004

Light is so fast that it takes less than 2 seconds to travel from the Earth to the moon. This blazing fast speed is what makes the Internet and other complex communications systems possible. But sometimes light needs to be slowed down so that signals can be routed in the right direction and order, converted from one form to another or synchronized properly.

Now, physicists at the National Institute of Standards and Technology (NIST) have proposed a new way to slow light down to almost one-millionth its usual speed--to the mere speed of a jet aircraft. As described in the Oct. 1 issue of Physical Review Letters,* the method eventually could help simplify and reduce the cost of high-speed optical communications. The paper presents mathematical calculations proving the existence of a new class of "soliton," a solitary light wave that can propagate over long distances without distortion even when moving very slowly through an ultracold gas.

Solitons first were discovered in the 1800s when a naval engineer observed a water wave travel more than a mile within a canal without dissipating. Light wave solitons generated within optical fibers are now the subject of intense research worldwide. Their very short, stable pulse shapes might be used to pack more information into fiber-optic communication systems. But when previously known forms of optical solitons are slowed down, attenuations and distortions (and therefore losses of data) occur quickly, before the light has traveled even 1 millimeter.

NIST physicists showed it is possible to use a very stable pulsed laser to create a soliton that travels slowly through a cryogenic gas of rubidium atoms for more than 5 centimeters without noticeable distortion. The scientists now plan to translate the theory into practical experiments. Currently, 300 kilometers of fiber are required to delay an optical signal for one thousandth of a second, whereas only a few centimeters of fiber might be needed using the new class of soliton.
The research was supported in part by the Office of Naval Research.

*Y. Wu and L. Deng, 2004, Ultraslow Optical Solitons in a Cold Four-State Medium, Physical Review Letters, Vol. 93. Issue 14, published online Sept. 28.

National Institute of Standards and Technology (NIST)

Related Light Articles from Brightsurf:

Light from rare earth: new opportunities for organic light-emitting diodes
Efficient and stable blue OLED is still a challenge due to the lack of emitter simultaneously with high efficiency and short excited-state lifetime.

Guiding light: Skoltech technology puts a light-painting drone at your fingertips
Skoltech researchers have designed and developed an interface that allows a user to direct a small drone to light-paint patterns or letters through hand gestures.

Painting with light: Novel nanopillars precisely control intensity of transmitted light
By shining white light on a glass slide stippled with millions of tiny titanium dioxide pillars, researchers at the National Institute of Standards and Technology (NIST) and their collaborators have reproduced with astonishing fidelity the luminous hues and subtle shadings of 'Girl With a Pearl Earring.'

Seeing the light: Researchers combine technologies for better light control
A new technology that can allow for better light control without requiring large, difficult-to-integrate materials and structures has been developed by Penn State researchers.

A different slant of light
Giant clams manipulate light to assist their symbiotic partner.

New light for plants
Scientists from ITMO in collaboration with their colleagues from Tomsk Polytechnic University came up with an idea to create light sources from ceramics with the addition of chrome: the light from such lamps offers not just red but also infrared (IR) light, which is expected to have a positive effect on plants' growth.

Scientists use light to accelerate supercurrents, access forbidden light, quantum world
Iowa State's Jigang Wang continues to explore using light waves to accelerate supercurrents to access the unique and potentially useful properties of the quantum world.

The power of light
As COVID-19 continues to ravage global populations, the world is singularly focused on finding ways to battle the novel coronavirus.

Seeing the light: MSU research finds new way novae light up the sky
An international team of astronomers from 40 institutes across 17 countries found that shocks cause most the brightness in novae.

Seeing the light: Astronomers find new way novae light up the sky
An international team of researchers, in a paper published today in Nature Astronomy, highlights a new way novae light up the sky: this is shocks from explosions that create the novae that cause most of the their brightness.

Read More: Light News and Light Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to