Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Advance by chemists may lead to better displays on laptop computers, cell phones

19.09.2007
UCLA chemists working at the nanoscale have developed a new, inexpensive means of forcing luminescent polymers to give off polarized light and of confining that light to produce polymer-based lasers.

The research, which could lead to a brighter polarized light source for LEDs in laptop computers, cell phones and other consumer electronics devices, currently appears in the advance online edition of the journal Nature Nanotechnology.

The research was conducted by UCLA professors of chemistry and California NanoSystems Institute members Sarah Tolbert and Benjamin J. Schwartz, and colleagues, including Hirokatsu Miyata, a research scientist with Canon’s Nanocomposite Research division in Japan. The research is federally funded by the National Science Foundation and the Office of Naval Research and privately funded by Canon.

The researchers have succeeded in taking semiconducting polymers — plastics that consist of long chains of atoms that work as semiconductors — and stretching them out in a silica (glass) host matrix so that they have new optical properties.

“If you have polymer chains that can wiggle like spaghetti, it’s hard to make them all point in the same direction,” Tolbert said. “What we do is take tiny, nanometer-sized holes in a piece of glass and force the polymer chains into the holes. The holes are so small that the spaghetti chains have no space to coil up. They have to lie straight, and all the chains end up pointing in the same direction.”

Because the chains point in the same direction, they absorb polarized light and give off polarized light. Lining up the polymer chains also provides advantages for laser technology, because all the chains can participate in the lasing process, and they can make the light polarized without the need for any external optical elements, Tolbert said.

As a postdoctoral fellow, Schwartz was one of the original discoverers in the 1990s that lasers could be made out of randomly oriented semiconducting polymer chains.

“Our new materials exploit the fact that the polymer chains are all lined up to make them into lasers that function very differently from lasers made out of random polymers,” Schwartz said.

The manner in which the polymer chains incorporate into the porous glass of the silica matrix helps to confine the light in the material, enhancing the lasing process by producing what is known as a “graded-index waveguide.” In most lasers, confining the light is typically done with external mirrors.

“Our materials don’t need mirrors to function as lasers, because the material that’s lasing is also serving to confine the light,” Schwartz said.

In combination, the alignment of the polymer chains and the confinement of the light make it 20 times easier for the new materials to lase than if a randomly oriented polymer sample were used. And because polymers can be dissolved easily in solvents, they are inexpensive to process. The glass host matrix with the aligned nanoscale pores is also inexpensive to produce.

“Usually polarized and cheap don’t go together,” Tolbert said.

The research opens the possibility of additional applications for the new materials as a brighter polarized source for displays in products with LED-type displays, including cell phones, laptops and Palm Pilots.

“If you take an inexpensive light source with which you could excite the aligned polymer chains and get the chains to reemit, you potentially have a more efficient way to generate polarized light.” Tolbert said. “This would allow displays to be brighter with less power consumption, and you could get longer battery life.”

Tolbert has collaborated with Canon for years on the development of this class of new materials.

Stuart Wolpert | EurekAlert!
Further information:
http://www.ucla.edu

More articles from Materials Sciences:

nachricht A new tool for discovering nanoporous materials
23.05.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Did you know that packaging is becoming intelligent through flash systems?
23.05.2017 | Heraeus Noblelight GmbH

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>