Physicists transmit visible light through miniature cable

January 8, 2007

Physicists at Boston College have beamed visible light through a cable hundreds of times smaller than a human hair, an achievement they anticipate will lead to advances in solar power and optical computing.

The discovery, details of which appear in the Jan. 8 issue of the journal Applied Physics Letters, defies a key principle that holds that light cannot pass through a hole much smaller than its wavelength. In fact, the BC team forced visible light, which has a wavelength of between 380-750 nanometers, to travel down a cable whose diameter is smaller than even the low end of that range.

The researchers say their achievement opens the door to a wide array of new technologies, from high-efficiency, inexpensive solar cells to microscopic light-based switching devices for use in optical computing. The technology could even be used to help some blind people see, the physicists say.

The advance builds upon the researchers' earlier invention of a microscopic antenna that captures visible light in much the same way radio antennae capture radio waves – a discovery they announced in 2004. This time, the BC physicists designed and fabricated a tiny version of the coaxial cable – the Information Age workhorse that carries telephone and Internet service along with hundreds of television and radio channels into millions of homes and businesses around the world.

"Our coax works just like the one in your house, except now for visible light," says Jakub Rybczynski, a research scientist in the Boston College Physics Department and the lead author of the APL article.

Coaxial cables are typically made up of a core wire surrounded by a layer of insulation, which in turn is surrounded by another metal sheath. This structure encloses energy and lets the cable transmit electromagnetic signals with wavelengths much larger than the diameter of the cable itself.

With this design in mind, the physicists developed what they called a "nanocoax" – a carbon nanotube-based coaxial cable with a diameter of about 300 nanometers. By comparison, the human hair is several hundred times wider.

The physicists designed their nanocoax so that the center wire protruded at one end, forming a light antenna. The other end was blunt, allowing the scientists to measure the light received by the antenna and transmitted through the medium.

The researchers were able to transmit both red and green light into the nanocoax and out the other end, indicating that the cable can carry a broad spectrum of visible light.

"The beauty of our nanocoax is that it lets us squeeze visible light through very small geometric dimensions. It also allows us to transmit light over a distance that is at least 10 times its wavelength," says BC Physics Prof. Kris Kempa, a co-author of the article.

Source: Boston College

Explore further: Researchers designing nuclear power plant that will float eight or more miles out to sea

Related Stories

SLAC scientists create twisted light

September 19, 2013

(Phys.org) —Scientists at SLAC have found a new method to create coherent beams of twisted light – light that spirals around a central axis as it travels. It has the potential to generate twisted light in shorter pulses, ...

Intergalactic GPS will guide you through the stars

March 10, 2015

Lost in the Universe? Need some precise navigation through the bulk of stars in the night sky? Don't worry, there will be an instrument for that - the Multi-Object Optical and Near-infrared Spectrograph (MOONS) at the European ...

A new, public view of the sky

January 7, 2015

For the first time, scientists and the public are beginning to see the large-scale structure of the universe, thanks to the Sloan Digital Sky Survey. UA scientists provide scientific expertise and crucial technology to the ...

Recommended for you

Researchers build bacteria's photosynthetic engine

July 29, 2015

Nearly all life on Earth depends on photosynthesis, the conversion of light energy into chemical energy. Oxygen-producing plants and cyanobacteria perfected this process 2.7 billion years ago. But the first photosynthetic ...

Rogue wave theory to save ships

July 29, 2015

Physicists have found an explanation for rogue waves in the ocean and hope their theory will lead to devices to warn ships and save lives.

Scientists unlock secrets of stars through aluminium

July 29, 2015

Physicists at the University of York have revealed a new understanding of nucleosynthesis in stars, providing insight into the role massive stars play in the evolution of the Milky Way and the origins of the Solar System.

New blow for 'supersymmetry' physics theory

July 27, 2015

In a new blow for the futuristic "supersymmetry" theory of the universe's basic anatomy, experts reported fresh evidence Monday of subatomic activity consistent with the mainstream Standard Model of particle physics.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.