Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > The Noise About Graphene

This image of a single suspended sheet of graphene taken with the TEAM 0.5, at Berkeley Lab’s National Center for Electron Microscopy shows individual carbon atoms (yellow) on the honeycomb lattice.
This image of a single suspended sheet of graphene taken with the TEAM 0.5, at Berkeley Lab’s National Center for Electron Microscopy shows individual carbon atoms (yellow) on the honeycomb lattice.

Abstract:
Berkeley Labs materials scientist Yuegang Zhang and colleagues at University of California, Los Angeles are moving toward more efficient devices by studying the ‘noise' in graphene nanoribbons

The Noise About Graphene

Berkeley, CA | Posted on October 18th, 2010

In last week's announcement of the Nobel Prize in Physics, the Royal Swedish Academy of Sciences lauded graphene's "exceptional properties that originate from the remarkable world of quantum physics." If it weren't hot enough before, this atomically thin sheet of carbon is now officially in the global spotlight.

The promise of graphene lies in the simplicity of its structure—a ‘chicken wire' lattice of carbon atoms just one layer thick. This sheet confines electrons in one dimension, forcing them to race across a plane. Such quantum confinement results in stellar electronic, mechanical and optical properties far beyond what silicon and other traditional semiconductor materials offer. What's more, if graphene's electrons were restricted in two dimensions, like in a nanoribbon, it could greatly benefit logic switching devices—the basis for computation units in today's computer chips.

Now, Berkeley Labs materials scientist Yuegang Zhang and colleagues at University of California, Los Angeles are moving toward more efficient devices by studying the ‘noise' in such graphene nanoribbons—one-dimensional strips of graphene with nanometer-scale widths.

"Atomically-thin graphene nanoribbons have provided an excellent platform for us to reveal the strong correlation between conductance fluctuation and the quantized electronic structures of quasi-one-dimensional systems," says Zhang, a staff scientist in the Inorganic Nanostructures Facility at the Molecular Foundry. "This method should have much broader use to understand quantum transport phenomena in other nanoelectronic or molecular devices."

Zhang and colleagues previously reported ways of fabricating films of graphene (1) and revealing low-frequency signal-to-noise ratios for graphene devices on a silica substrate (2). In the current study, the team made graphene nanoribbons using a nanowire mask-based fabrication technique. By measuring the conductance fluctuation, or ‘noise' of electrons in graphene nanoribbons, the researchers directly probed the effect of quantum confinement in these structures. Their findings map the electronic band structure of these graphene nanoribbons using a robust electrical probing method. This method can be further applied to a wide array of nanoscale materials, including graphene-based electronic devices.

"It amazes us to observe such a clear correlation between the noise and the band structure of these graphene nanomaterials," says lead author Guangyu Xu, a physicist at University of California, Los Angeles. "This work adds strong support to the quasi-one-dimensional subband formation in graphene nanoribbons, in which our method turns out to be much more robust than conductance measurement."

A paper reporting this research titled, "Enhanced conductance fluctuation by quantum confinement effect in graphene nanoribbons," appears in Nano Letters and is available to subscribers online . Co-authoring the paper with Zhang and Xu were Carlos Torres, Jr., Emil Song, Jianshi Tang, Jingwei Bai, Xiangfeng Duan and Kang L. Wang.

Portions of this work at the Molecular Foundry were supported by DOE's Office of Science.

The Molecular Foundry is one of the five DOE Nanoscale Science Research Centers (NSRCs), national user facilities for interdisciplinary research at the nanoscale, supported by the DOE Office of Science. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE's Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos National Laboratories. For more information about the DOE NSRCs, please visit nano.energy.gov.

(1) newscenter.lbl.gov/feature-stories/2010/04/08/graphene-films/
(2) newscenter.lbl.gov/news-releases/2010/08/06/noise-in-graphene/

####

About Lawrence Berkeley National Laboratory
Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California.

Visit our website at www.lbl.gov

For more information, please click here

Contacts:
Aditi Risbud
(510) 486-4861

Copyright © Berkeley Lab

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

University of Akron researchers find thin layers of water can become ice-like at room temperature: Results could lead to an assortment of anti-friction solutions August 30th, 2016

Nanocatalysis for organic chemistry: This research article by Dr. Qien Xu et al. is published in Current Organic Chemistry, Volume 20, Issue 19, 2016 August 30th, 2016

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Meteorite impact on a nano scale August 29th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Analog DNA circuit does math in a test tube: DNA computers could one day be programmed to diagnose and treat disease August 25th, 2016

New approach to determining how atoms are arranged in materials August 25th, 2016

Johns Hopkins scientists track metabolic pathways to find drug combination for pancreatic cancer August 25th, 2016

New electrical energy storage material shows its power: Nanomaterial combines attributes of both batteries and supercapacitors August 25th, 2016

Possible Futures

Nanocatalysis for organic chemistry: This research article by Dr. Qien Xu et al. is published in Current Organic Chemistry, Volume 20, Issue 19, 2016 August 30th, 2016

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Designing ultrasound tools with Lego-like proteins August 29th, 2016

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Academic/Education

AIM Photonics Announces Release of Process Design Kit (PDK) for Integrated Silicon Photonics Design August 25th, 2016

Nanotech Security Featured by Simon Fraser University: Company's Anti-Counterfeiting Technology Developed With the Help of University's 4D LABS Materials Research Institute August 21st, 2016

W.M. Keck Foundation awards Cal State LA a $375,000 research and education grant August 4th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

Chip Technology

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Analog DNA circuit does math in a test tube: DNA computers could one day be programmed to diagnose and treat disease August 25th, 2016

Nanoelectronics

Light and matter merge in quantum coupling: Rice University physicists probe photon-electron interactions in vacuum cavity experiments August 24th, 2016

New microchip demonstrates efficiency and scalable design: Increased power and slashed energy consumption for data centers August 24th, 2016

Down to the wire: ONR researchers and new bacteria August 18th, 2016

Smarter self-assembly opens new pathways for nanotechnology: Brookhaven Lab scientists discover a way to create billionth-of-a-meter structures that snap together in complex patterns with unprecedented efficiency August 9th, 2016

Announcements

University of Akron researchers find thin layers of water can become ice-like at room temperature: Results could lead to an assortment of anti-friction solutions August 30th, 2016

Nanocatalysis for organic chemistry: This research article by Dr. Qien Xu et al. is published in Current Organic Chemistry, Volume 20, Issue 19, 2016 August 30th, 2016

Continuous roll-process technology for transferring and packaging flexible LSI August 29th, 2016

Meteorite impact on a nano scale August 29th, 2016

Quantum nanoscience

Light and matter merge in quantum coupling: Rice University physicists probe photon-electron interactions in vacuum cavity experiments August 24th, 2016

Prototype chip could help make quantum computing practical: Built-in optics could enable chips that use trapped ions as quantum bits August 9th, 2016

Diamond-based light sources will lay a foundation for quantum communications of the future: Electrified quantum diamond can become the heart of quantum networks and computers of the future August 7th, 2016

Scientists discover light could exist in a previously unknown form August 6th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic