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 WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf

nachricht First form of therapy for childhood dementia CLN2 developed
25.04.2018 | Universitätsklinikum Hamburg-Eppendorf

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: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

Im Focus: Light-induced superconductivity under high pressure

A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Supersonic waves may help electronics beat the heat

18.05.2018 | Power and Electrical Engineering

Keeping a Close Eye on Ice Loss

18.05.2018 | Information Technology

CrowdWater: An App for Flood Research

18.05.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>