Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Solitons could power molecular electronics, artificial muscles

10.07.2006
Scientists have discovered something new about exotic particles called solitons.

Since the 1980s, scientists have known that solitons can carry an electrical charge when traveling through certain organic polymers. A new study now suggests that solitons have intricate internal structures.

Scientists may one day use this information to put the particles to work in molecular electronics and artificial muscles, said Ju Li, assistant professor of materials science and engineering at Ohio State University.

Li explained that each soliton is made up of an electron surrounded by other particles called phonons. Just as a photon is a particle of light energy, a phonon is a particle of vibrational energy.

The new study suggests that the electron inside a soliton can attain different energy states, just like the electron in a hydrogen atom.

"While we know that such internal electronic structures exist in all atoms, this is the first time anyone has shown that such structures exist in a soliton," Li said.

The soliton's quantum mechanical properties -- including these newly discovered energy states -- are important because they affect how the particle carries a charge through organic materials such as conducting polymers at the molecular level.

"These extra electronic states will have an effect -- we just don't know right now if it will be for better or worse," he said.

Li and his longtime collaborators from MIT published their findings in a recent issue of the Proceedings of the National Academy of Sciences (PNAS).

The name "soliton" is short for "solitary wave." Though scientists often treat particles such as electrons as waves, soliton waves are different. Ordinary electron waves spread out and diminish over time, and soliton waves don't.

"It's like when you make a ripple in water -- it quickly spreads and disappears," Li said. "But a soliton is a strange kind of object. Once it is made, it maintains its character for a long time."

In fiber optics, normal light waves gradually flatten out; unless the signal is boosted periodically, it disappears. In contrast, solitonic light waves retain their structure and keep going without assistance. Some telecommunication companies have exploited that fact by using solitons to cheaply send signals over long distances.

Before solitons can be fully exploited in a wider range of applications, scientists must learn more about their basic properties, Li said. He's especially interested in how solitons carry a charge through conducting polymers, which consist of long, skinny chains of molecules.

The tiny chains are practically one-dimensional, and this calls some strange physics into play, Li said.

In their PNAS paper, Li and MIT colleagues Xi Lin, Clemens Först, and Sidney Yip describe a detailed calculation of what happens to solitons at a quantum-mechanical level as they travel along a chain of the organic polymer polyacetylene.

Their mathematical model builds upon a 1979 model called the Su-Schrieffer-Heeger (SSH) model. Alan Heeger, a University of California, Santa Barbara physicist who discovered solitons, won the Nobel Prize in 2000 for his pioneering work on conducting polymers.

Li said the new work extends the SSH model by including the full flexibility of the polymer chain, as well as interactions between electrons.

The finding will likely affect the development of molecular electronics -- devices built from individual molecules.

Because polymer chains tend to bend and twist as solitons pass through them, scientists have wondered whether solitons could be used to power artificial muscles for high-tech robots and devices to aid human mobility. Such muscles would be made of organic polymers, and flex in response to light or electrochemical stimulation.

"If fully understood, solitons may also be harnessed to drive molecular motors in nanotechnology," Li said.

This work was mainly funded by Honda R&D Co., Ltd., with computing resources provided by the Ohio Supercomputer Center.

Ju Li | EurekAlert!
Further information:
http://www.osu.edu

More articles from Studies and Analyses:

nachricht The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

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,...

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

From Hannover around the world and to the Mars: LZH delivers laser for ExoMars 2020

21.11.2017 | Physics and Astronomy

Borophene shines alone as 2-D plasmonic material

21.11.2017 | Materials Sciences

Penn study identifies new malaria parasites in wild bonobos

21.11.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>