Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Key Property of Graphene Sustained Over Wide Ranges of Density and Energy

Abstract:
A collaboration led by researchers from the NIST Center for Nanoscale Science and Technology has shown for the first time that charge carriers in graphene continue to behave as massless particles, like photons, over wider ranges of both density and energy than previously measured or modeled.* Graphene, a single layer of carbon atoms, is a material of great scientific and technological interest in part because it conducts electrons at high speed. However, in order for graphene to achieve its promise as a component of future electronic devices, it is important to understand at a fundamental level how charge carriers in the material interact with each other.

Key Property of Graphene Sustained Over Wide Ranges of Density and Energy

Gaithersburg, MD | Posted on November 15th, 2012

The researchers used scanning tunneling spectroscopy measurements of the magnetic quantum energy levels of the graphene charge carriers to determine the changes in velocity of the charge carriers. Using a CNST-developed technique called "gate mapping scanning tunneling spectroscopy," the researchers measured the energy levels as they changed the density of the carriers in the graphene by applying different potentials between a conducting gate and the two-dimensional graphene sheet. They established that the graphene carriers retain a proportional relationship between energy and momentum—a "linear dispersion" characteristic of massless particles—across an unexpectedly broad range of energies and densities, from electrons to holes. They were also able to show that when the density of carriers in graphene is lowered, the effect of each electron on other electrons increases, resulting in higher velocities than expected. These surprising results are important both for understanding the physics of future graphene devices and because they will help guide the development of more accurate theoretical models of the interactions between electrons in two-dimensional systems.

*Renormalization of the graphene dispersion velocity determined from scanning tunneling spectroscopy, J. Chae, S. Jung, A. F. Young, C. R. Dean, L. Wang, Y. Gao, K. Watanabe, T. Taniguchi, J. Hone, K. L. Shepard, P. Kim, N. B. Zhitenev, and J. A. Stroscio, Physical Review Letters 109, 116802 (2012).

####

About National Institute of Standards and Technology (NIST)
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

For more information, please click here

Contacts:
Joseph Stroscio
301-975-3716

Copyright © National Institute of Standards and Technology (NIST)

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 Links

NIST Publication Database:

Journal Web Site:

Related News Press

Laboratories

Speedy ion conduction in solid electrolytes clears road for advanced energy devices May 5th, 2016

Exploring phosphorene, a promising new material April 29th, 2016

NREL finds nanotube semiconductors well-suited for PV systems April 27th, 2016

News and information

Speedy ion conduction in solid electrolytes clears road for advanced energy devices May 5th, 2016

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Clues on the path to a new lithium battery technology: Charging produces highly reactive singlet oxygen in lithium air batteries May 5th, 2016

Unique nano-capsules promise the targeted drug delivery: Russian scientists created unique nano-capsules for the targeted drug delivery May 5th, 2016

Imaging

Oxford Instruments Asylum Research and McGill University Announce the McGill AFM Summer School and Workshop, May 12-13, 2016 May 4th, 2016

The intermediates in a chemical reaction photographed 'red-handed' Researchers at the UPV/EHU-University of the Basque Country have for the first time succeeded in imaging all the steps in a complex organic reaction and have resolved the mechanisms that explain it May 4th, 2016

New tool allows scientists to visualize 'nanoscale' processes May 4th, 2016

FEI Launches Apreo – Industry-Leading Versatile, High-Performance SEM: The Apreo SEM provides high-resolution surface information with excellent contrast, and the flexibility to accommodate a large range of samples, applications and conditions May 4th, 2016

Graphene/ Graphite

Cooling graphene-based film close to pilot-scale production April 30th, 2016

University of Illinois researchers create 1-step graphene patterning method April 27th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Speedy ion conduction in solid electrolytes clears road for advanced energy devices May 5th, 2016

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Clues on the path to a new lithium battery technology: Charging produces highly reactive singlet oxygen in lithium air batteries May 5th, 2016

Molybdenum disulfide holds promise for light absorption: Rice researchers probe light-capturing properties of atomically thin MoS2 May 5th, 2016

Discoveries

Speedy ion conduction in solid electrolytes clears road for advanced energy devices May 5th, 2016

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Unique nano-capsules promise the targeted drug delivery: Russian scientists created unique nano-capsules for the targeted drug delivery May 5th, 2016

Molybdenum disulfide holds promise for light absorption: Rice researchers probe light-capturing properties of atomically thin MoS2 May 5th, 2016

Announcements

Speedy ion conduction in solid electrolytes clears road for advanced energy devices May 5th, 2016

Engineers create a better way to boil water -- with industrial, electronics applications May 5th, 2016

Clues on the path to a new lithium battery technology: Charging produces highly reactive singlet oxygen in lithium air batteries May 5th, 2016

Unique nano-capsules promise the targeted drug delivery: Russian scientists created unique nano-capsules for the targeted drug delivery May 5th, 2016

Tools

Oxford Instruments Asylum Research and McGill University Announce the McGill AFM Summer School and Workshop, May 12-13, 2016 May 4th, 2016

The intermediates in a chemical reaction photographed 'red-handed' Researchers at the UPV/EHU-University of the Basque Country have for the first time succeeded in imaging all the steps in a complex organic reaction and have resolved the mechanisms that explain it May 4th, 2016

New tool allows scientists to visualize 'nanoscale' processes May 4th, 2016

FEI Launches Apreo – Industry-Leading Versatile, High-Performance SEM: The Apreo SEM provides high-resolution surface information with excellent contrast, and the flexibility to accommodate a large range of samples, applications and conditions May 4th, 2016

Quantum nanoscience

A compact, efficient single photon source that operates at ambient temperatures on a chip: Highly directional single photon source concept is expected to lead to a significant progress in producing compact, cheap, and efficient sources of quantum information bits for future appls May 3rd, 2016

Quantum sensors for high-precision magnetometry of superconductors May 3rd, 2016

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

The atom without properties April 22nd, 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