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 A better way to weigh millions of solitary stars
15.12.2017 | Vanderbilt University

nachricht A chip for environmental and health monitoring
15.12.2017 | Friedrich-Alexander-Universität Erlangen-Nürnberg

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: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>