Featured Research

from universities, journals, and other organizations

Researchers design nanometer-scale material that can speed up, squeeze light

Date:
April 29, 2013
Source:
Missouri University of Science and Technology
Summary:
In a process one researcher compares to squeezing an elephant through a pinhole, researchers have designed a way to engineer atoms capable of funneling light through ultra-small channels.

The cross-section of a 100-nanometer-long “meta-atom” of gold and silicon oxide. Researchers say the meta-atom is capable of straightening and speeding up light waves.
Credit: Image courtesy of Missouri University of Science and Technology

In a process one researcher compares to squeezing an elephant through a pinhole, researchers at Missouri University of Science and Technology have designed a way to engineer atoms capable of funneling light through ultra-small channels.

Their research is the latest in a series of recent findings related to how light and matter interact at the atomic scale, and it is the first to demonstrate that the material -- a specially designed "meta-atom" of gold and silicon oxide -- can transmit light through a wide bandwidth and at a speed approaching infinity. The meta-atoms' broadband capability could lead to advances in optical devices, which currently rely on a single frequency to transmit light, the researchers say.

"These meta-atoms can be integrated as building blocks for unconventional optical components with exotic electromagnetic properties over a wide frequency range," write Dr. Jie Gao and Dr. Xiaodong Yang, assistant professors of mechanical engineering at Missouri S&T, and Dr. Lei Sun, a visiting scholar at the university. The researchers describe their atomic-scale design in the latest issue of the journal Physical Review B.

The researchers created mathematical models of the meta-atom, a material 100 nanometers wide and 25 nanometers tall that combined gold and silicon oxide in stairstep fashion. A nanometer is one billionth of a meter and visible only with the aid of a high-power electron microscope.

In their simulations, the researchers stacked 10 of the meta-atoms, then shot light through them at various frequencies. They found that when light encountered the material in a range between 540 terahertz and 590 terahertz, it "stretched" into a nearly straight line and achieved an "effective permittivity" known as epsilon-near-zero.

Effective permittivity refers to the ratio of light's speed through air to its speed as it passes through a material. When light travels through glass, for instance, its effective permittivity is 2.25. Through air or the vacuum of outer space, the ratio is one. That ratio is what is typically referred to as the speed of light.

As light passes through the engineered meta-atoms described by Gao and Yang, however, its effective permittivity reaches a near-zero ratio. In other words, through the medium of these specially designed materials, light actually travels faster than the speed of light. It travels "infinitely fast" through this medium, Yang says.

The meta-atoms also stretch the light. Other materials, such as glass, typically compress optical waves, causing diffraction.

This stretching phenomenon means that "waves of light could tunnel through very small holes," Yang says. "It is like squeezing an elephant through an ultra-small channel."

The wavelength of light encountering a single meta-atom is 500 nanometers from peak to peak, or five times the length of Gao and Yang's specially designed meta-atoms, which are 100 nanometers in length. While the Missouri S&T team has yet to fabricate actual meta-atoms, they say their research shows that the materials could be built and used for optical communications, image processing, energy redirecting and other emerging fields, such as adaptive optics.

Last year, Albert Polman at the FOM Institute for Atomic and Molecular Physics in Amsterdam and Nader Engheta, an electrical engineer at the University of Pennsylvania, developed a tiny waveguide device in which light waves of a single wavelength also achieved epsilon-near-zero. But the Missouri S&T researchers' work is the first to demonstrate epsilon-near-zero in a broadband of 50 terahertz.

"The design is practical and realistic, with the potential to fabricate actual meta-atoms," says Gao. Adds Yang: "With this research, we filled the gap from the theoretical to the practical."

Through a process known as electron-beam deposition, the researchers have built a thin-film wafer from 13 stacked meta-atoms. But those materials were uniform in composition rather than arranged in the stairstep fashion of their modeled meta-atoms.


Story Source:

The above story is based on materials provided by Missouri University of Science and Technology. The original article was written by Andrew Careaga. Note: Materials may be edited for content and length.


Journal Reference:

  1. Lei Sun, Jie Gao, Xiaodong Yang. Broadband epsilon-near-zero metamaterials with steplike metal-dielectric multilayer structures. Physical Review B, 2013; 87 (16) DOI: 10.1103/PhysRevB.87.165134

Cite This Page:

Missouri University of Science and Technology. "Researchers design nanometer-scale material that can speed up, squeeze light." ScienceDaily. ScienceDaily, 29 April 2013. <www.sciencedaily.com/releases/2013/04/130429094646.htm>.
Missouri University of Science and Technology. (2013, April 29). Researchers design nanometer-scale material that can speed up, squeeze light. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2013/04/130429094646.htm
Missouri University of Science and Technology. "Researchers design nanometer-scale material that can speed up, squeeze light." ScienceDaily. www.sciencedaily.com/releases/2013/04/130429094646.htm (accessed October 22, 2014).

Share This



More Matter & Energy News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
China Airlines Swanky New Plane

China Airlines Swanky New Plane

Buzz60 (Oct. 21, 2014) China Airlines debuted their new Boeing 777, and it's more like a swanky hotel bar than an airplane. Enjoy high-tea, a coffee bar, and a full service bar with cocktails and spirits, and lie-flat in your reclining seats. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
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:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

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