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 Some brain tumors may respond to immunotherapy, new study suggests
11.12.2018 | Columbia University Irving Medical Center

nachricht Climate change and air pollution damaging health and causing millions of premature deaths
30.11.2018 | 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: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

New discoveries predict ability to forecast dementia from single molecule

12.12.2018 | Health and Medicine

CCNY-Yale researchers make shape shifting cell breakthrough

12.12.2018 | Physics and Astronomy

Pain: Perception and motor impulses arise in the brain independently of one another

12.12.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>