Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'Metasurfaces' to usher in new optical technologies

15.03.2013
New optical technologies using "metasurfaces" capable of the ultra-efficient control of light are nearing commercialization, with potential applications including advanced solar cells, computers, telecommunications, sensors and microscopes.
The metasurfaces could make possible "planar photonics" devices and optical switches small enough to be integrated into computer chips for information processing and telecommunications, said Alexander Kildishev, associate research professor of electrical and computer engineering at Purdue University.

"I think we know enough at this point that we can realistically start to develop prototypes of devices for some applications," he said.

The promise of metasurfaces is described in an article appearing Friday (March 15) in the journal Science. The article was co-authored by Kildishev; Alexandra Boltasseva, an assistant professor of electrical and computer engineering; and Vladimir M. Shalaev, scientific director of nanophotonics at Purdue's Birck Nanotechnology Center and a distinguished professor of electrical and computer engineering.

The metasurfaces are extremely thin films of "metamaterials," assemblies that contain features, patterns or elements such as tiny antennas or alternating layers of oxides that enable an unprecedented control of light. Under development for about 15 years, the metamaterials owe their unusual potential to precision design on the scale of nanometers.

Optical nanophotonic circuits might harness clouds of electrons called "surface plasmons" to manipulate and control the routing of light in devices too tiny for conventional lasers.

The metasurfaces are typically created using electron-beam lithography or focused ion beam milling and may also be made of materials that are compatible with existing semiconductor manufacturing and industrial processes.

"That is one of the attractive features of metasurfaces," Kildishev said. "If we use certain types of plasmonic material, they can be integrated into existing semiconductor processes, which makes them practical for commercialization."

Plasmonic metamaterials are promising for various advances, including a possible "hyperlens" that could make optical microscopes 10 times more powerful; advanced chemical sensors; new types of light-harvesting systems for more efficient solar cells; computers and consumer electronics that use light instead of electronic signals to process information; and a cloak of invisibility.

The metasurfaces can be combined with thin sheets of carbon called graphene.

"If you apply voltage the optical properties of graphene change, and if you couple a graphene layer with a metasurface, these properties then change dramatically," Kildishev said.

Metasurfaces could make it possible to use single photons – the tiny particles that make up light – for switching and routing in future computers. While using photons would dramatically speed up computers and telecommunications, conventional photonic devices cannot be miniaturized because the wavelength of light is too large to fit in tiny components needed for integrated circuits.

Nanostructured metamaterials, however, could make it possible to reduce the size of photons and the wavelength of light, allowing the creation of new types of nanophotonic devices, Shalaev said.

Some of the new materials may have applications involving near-infrared light, the range of the spectrum critical for telecommunications and fiberoptics. Other materials also might work for light in the spectrum's visible range.
Unlike natural materials, metamaterials may possess an index of refraction less than one or less than zero. Refraction occurs as electromagnetic waves, including light, bend when passing from one material into another. It causes the bent-stick-in-water effect, which occurs when a stick placed in a glass of water appears crooked when viewed from the outside. Being able to create materials with an index of refraction that's negative or between one and zero promises a range of potential breakthroughs in a new field called transformation optics.

Development of new technologies using metamaterials has been hindered by two major limitations: too much light is "lost," or absorbed by metals such as silver and gold contained in the metamaterials, and the materials need to be more precisely tuned so that they possess the proper index of refraction. Ultrathin metasurfaces made of novel low-loss plasmonic material components is a promising way to address this challenge.

Researchers are working to replace silver and gold in materials that are created either by making semiconductors more metallic by adding metal impurities to them; or adding non-metallic elements to metals, in effect making them less metallic. Examples of these materials include transparent conducting oxides and titanium nitride, Boltasseva said.

Writer: Emil Venere, 765-494-4709, venere@purdue.edu
Sources: Alexander Kildishev, 765-496-3196, kildishev@purdue.edu

Vladimir Shalaev, 765-494-9855, shalaev@ecn.purdue.edu

Alexandra Boltasseva, 765-494-0301, aeb@purdue.edu

Note to Journalists: A copy of the article is available by contacting the Science Press Package team at 202-326-6440, scipak@aaas.org

Emil Venere | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Power and Electrical Engineering:

nachricht A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes
20.07.2018 | Science China Press

nachricht Future electronic components to be printed like newspapers
20.07.2018 | Purdue University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>