Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

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

National Science Foundation Selects SUNY Poly CNSE for Expanded $2.1M Northeast Advanced Technological Education Center: NSF Center Locates to NanoCollege in Support of Flourishing Tech Industry in NYS September 1st, 2015

RUSNANOPRIZE Directorate Announces New Deadline for Nominations Submission – September 11, 2015 September 1st, 2015

$200K Awarded to Develop In Vitro Lung Test for Toxicity of Inhaled Nanomaterials: In Vitro Lung Test Designed to Protect Human Health and Replace Animal Testing September 1st, 2015

Hot electrons point the way to perfect light absorption: Physicists study how to achieve perfect absorption of light with the help of rough ultrathin films September 1st, 2015

Govt.-Legislation/Regulation/Funding/Policy

Sustainable nanotechnology center September 1st, 2015

National Science Foundation Selects SUNY Poly CNSE for Expanded $2.1M Northeast Advanced Technological Education Center: NSF Center Locates to NanoCollege in Support of Flourishing Tech Industry in NYS September 1st, 2015

An engineered surface unsticks sticky water droplets August 31st, 2015

New material science research may advance tech tools August 31st, 2015

Possible Futures

Sediment dwelling creatures at risk from nanoparticles in common household products August 13th, 2015

Harris & Harris Group Reports Financial Statements as of June 30, 2015, and Announces a Stock Repurchase Program August 10th, 2015

Molecular trick alters rules of attraction for non-magnetic metals August 5th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Academic/Education

Sustainable nanotechnology center September 1st, 2015

National Science Foundation Selects SUNY Poly CNSE for Expanded $2.1M Northeast Advanced Technological Education Center: NSF Center Locates to NanoCollege in Support of Flourishing Tech Industry in NYS September 1st, 2015

Announcing Oxford Instruments and School of Physics signing a Memorandum of Understanding August 26th, 2015

Kwansei Gakuin University in Hyogo, Japan, uses Raman microscopy to study crystallographic defects in silicon carbide wafers August 25th, 2015

Chip Technology

Nanometrics to Participate in the Citi 2015 Global Technology Conference August 26th, 2015

Kwansei Gakuin University in Hyogo, Japan, uses Raman microscopy to study crystallographic defects in silicon carbide wafers August 25th, 2015

A little light interaction leaves quantum physicists beaming August 25th, 2015

'Magic' sphere for information transfer: Professor at the Lomonosov Moscow State University made the «magic» sphere for information transfer August 24th, 2015

Nanoelectronics

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

'Quantum dot' technology may help light the future August 19th, 2015

Surprising discoveries about 2-D molybdenum disulfide: Berkeley Lab researchers use award-winning campanile probe on promising semiconductor August 15th, 2015

Better together: Graphene-nanotube hybrid switches August 3rd, 2015

Announcements

$200K Awarded to Develop In Vitro Lung Test for Toxicity of Inhaled Nanomaterials: In Vitro Lung Test Designed to Protect Human Health and Replace Animal Testing September 1st, 2015

Hot electrons point the way to perfect light absorption: Physicists study how to achieve perfect absorption of light with the help of rough ultrathin films September 1st, 2015

Using DNA origami to build nanodevices of the future September 1st, 2015

Nanotech could rid cattle of ticks, with less collateral damage September 1st, 2015

Quantum nanoscience

Scientists 'squeeze' light one particle at a time: A team of scientists have measured a bizarre effect in quantum physics, in which individual particles of light are said to have been 'squeezed' -- an achievement which at least one textbook had written off as hopeless September 1st, 2015

Seeing quantum motion August 30th, 2015

Quantum diffraction at a breath of nothing: Physicists build stable diffraction structure in atomically thin graphene August 25th, 2015

Southampton scientists find new way to detect ortho-para conversion in water August 25th, 2015

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