Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UC San Diego Physicists Reveal Secrets of Newest Form of Carbon

12.06.2008
Using one of the world’s most powerful sources of man-made radiation, physicists from UC San Diego, Columbia University and Lawrence Berkeley National Laboratory have uncovered new secrets about the properties of graphene—a form of pure carbon that may one day replace the silicon in computers, televisions, mobile phones and other common electronic devices.

Graphene—a single layer of carbon atoms arranged in a honeycombed lattice—has a number of advantages over silicon. Because it is an optically transparent conductor of electricity, graphene could be used to replace current liquid crystal displays that employ thin metal-oxide films based on indium, a rare metal that is becoming increasingly expensive and likely to be in short supply within a decade. The problem for scientists is that not much is known about its optical and electronic properties because graphene, which was discovered only four years ago, has resisted traditional forms of spectroscopy.

In this week’s advance online publication of the journal Nature-Physics, the physicists report that they used the Advanced Light Source at the Berkeley lab—one of the most powerful and versatile sources of electromagnetic radiation, from the infrared to x-ray region, in the world—to reveal some of those secrets. The researchers said that their study shows that the electrons in graphene strongly interact not only with the honeycomb lattice, but also with each other.

“Infrared and optical experiments are capable of providing some of the most valuable insights into the electronic properties of materials, including interactions between electrons in a material,” said Dimitri Basov, a professor of physics at UC San Diego who headed the project. “But it was extremely difficult to measure the absorption of light in a single monolayer of graphene, because not much light is absorbed. To do this, we had to start with a very bright light. It was spectroscopy to the extreme.”

The radiation from the Advanced Light Source, or ALS, is about 100 million times brighter than that from the most powerful X-ray tube, the source used in a dentist's machine. High brightness means that the radiation is highly concentrated and many photons per second can be directed onto a tiny area of a material.

Just as dentists use x rays to see inside your gums, scientists use the ALS’s radiation—generated by accelerating electrons around a circular racetrack at close to the speed of light—to look inside materials.

“It took some difficult experimental work to make this measurement,” said Basov. “It was by far the most complicated measurement we have ever done.”

Zhiqiang Li, a UCSD physics graduate student in Basov’s group, was the first author of the paper. Other principal investigators involved in the discovery were Michael Martin, staff scientist at the Berkeley laboratory’s ALS; Philip Kim, an associate professor of physics at Columbia University; and Horst Stormer, a professor of physics at Columbia and winner of the 1998 Nobel Prize in Physics.

Funding for the project was provided by the U.S. Department of Energy.

Kim McDonald | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Physics and Astronomy:

nachricht First chip-scale broadband optical system that can sense molecules in the mid-IR
24.05.2018 | Columbia University School of Engineering and Applied Science

nachricht Nuclear physicists leap into quantum computing with first simulations of atomic nucleus
24.05.2018 | DOE/Oak Ridge National Laboratory

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: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

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...

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

When corals eat plastics

24.05.2018 | Ecology, The Environment and Conservation

Surgery involving ultrasound energy found to treat high blood pressure

24.05.2018 | Medical Engineering

First chip-scale broadband optical system that can sense molecules in the mid-IR

24.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>