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.
Greg Frost | EurekAlert!
Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich
Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine