Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

An aerial for light

17.02.2003


Austrian physicists report unusual light-metal interaction



A team under Professor Franz Aussenegg at the University of Graz in Austria is looking into unusual interactions between light and submicroscopic metal particles. The physicists’ findings represent a major advance towards the development of improved data storage media and optical sensors. They also confirmed theoretical predictions and merited publication in 13 international scientific journals. These are the impressive results of a two-year project funded by the Austrian Science Fund (FWF) that has been investigating the nano-cosmos.

“There’s plenty of room at the bottom,” said American Nobel Prizewinner Richard P. Feynman back in 1959. By “the bottom” he meant the world of things that are too small to see, and his point is proved by today’s computer chips, which are constantly becoming smaller yet can process increasing amounts of data, and the steadily growing capacity of CDs and DVDs. However data processing in ever tinier dimensions calls for new technologies. One of these, nano-optics, which uses light, is being researched into by Prof. Aussenegg’s team at the University of Graz Institute for Experimental Physics in Austria.


“For physical reasons guiding light with the help of lenses, mirrors or prisms is no longer possible when you get down to millionths of millimetres — the nanoworld,” said the Institute’s director, Aussenegg. “But this is the level where light — or to be more precise, optoelectrical fields — can be led through solid materials. In principle, it’s like guiding radio and TV signals through aerials and cables.” This is possible because light enters into a fascinating interaction with metal at the nanometre level. It is no longer reflected but instead excites electrons near the surface of the metal, causing them to oscillate. For a short time the light is “captured“ in the metallic structure, as an electrical field. If this “surface plasmon” state lasts long enough the optoelectrical oscillations in the metal can be channelled, as though they were travelling along a nanoscopic wire. This is crucial to the prospects of nano-optics as a practical technology.

The Graz project, completed in December 2002, succeeded in demonstrating that it is possible to influence the duration of the oscillating state of electrons near the surface of a grating-like structure of metal particles that are a few millionths of a millimetre apart from each other. The FWF backed project investigated the influence of the precise dimensions of gold and silver gratings. It provided convincing confirmation of the theoretical prediction that the right ratio of the spacing of the metal particles and their size to the wavelength of the light would quadruple the duration of the oscillation.

The team’s findings have laid the groundwork for the use of light as an alternative to electrotechnology in telecommunications engineering, data processing and data storage. The results have already opened the way for improved data storage media and optical sensors. The researchers’ work has attracted widespread attention, as shown by an article published on 24 October in the online version of Britain’s Economist magazine which spoke of a “significant step towards properly integrated optoelectronics”. Again and again, the origins of industrial revolutions have lain in fundamental research, and the breakthrough in Graz could be the start of another.

Bildunterschrift: The principle of the surface plasmon: light spreads outwards on a nanoscopic metal surface similarly to a wave in water.

Alexandra Stolba | alfa

More articles from Physics and Astronomy:

nachricht Taking a spin on plasma space tornadoes with NASA observations
20.11.2017 | NASA/Goddard Space Flight Center

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>