Is graphene the best quantum resistance standard?

Sep 19, 2011
Graphene has the potential to surpass conventional materials in many applications including quantum resistance metrology

New research from NPL's Quantum Detection Group presents the most precise measurements of the quantum Hall effect ever made, using the two-dimensional material graphene.

The quantum Hall effect defines a relationship between two fundamental physical constants: the Planck constant h and e. It is vitally important for a 'quantum-based' redefinition of the SI units of mass (kilogram) and current (ampere) based on these constants. Experiments are needed to test the quantum Hall effect in different materials in order to prove whether or not it is truly universal.

This research compared the quantum Hall effect in graphene with that observed in a traditional . Graphene is hotly tipped to surpass in many important applications, partly due to its extraordinary .

The results confirmed that the quantum Hall effect is truly universal with an uncertainty level of several parts in 1011, supporting the redefinition of the kilogram and ampere. They also suggest that graphene should be the material of choice for quantum resistance metrology.

JT Janssen, NPL Science Fellow and author of the research, said:

"Many metrology laboratories around the world have been striving to do this experiment and it is a real achievement that the NPL team and its co-workers were the first to get this key result. It turns out that the in graphene is very robust and easy to measure - not bad for a material that was only discovered 6 years ago."

The research was conducted in collaboration with the Bureau International des Poids et Mesures, Chalmers University of Technology (Sweden), Lancaster University (UK) and Linköping University (Sweden).


Explore further: Longer distance quantum teleportation achieved

More information: Read the full paper.

add to favorites email to friend print save as pdf

Related Stories

Switchyard for single electrons

Feb 25, 2008

German scientists achieved to transfer very small charge "packets", comprising a well-defined number of few electrons, between metallic electrons precisely by using a single-electron pump. A single-electron transistor, being ...

Observing the Quantum Hall Effect in 'Real' Space

Jan 12, 2009

(PhysOrg.com) -- When water transforms into steam, or magnetized iron changes to demagnetized iron, Katsushi Hashimoto explains to PhysOrg.com, a phase transition is taking place: “Classical phase transitions…often share ...

Shining light on graphene sensors

Jan 10, 2011

National Physical Laboratory, together with an international team of scientists, have published research showing how light can be used to control graphene's electrical properties. This advance is an important ...

Recommended for you

Quantum mechanics to charge your laptop?

Sep 18, 2014

Top scientists from UC Berkeley and MIT found the expertise they lacked at FIU. They invited Sakhrat Khizroev, a professor with appointments in both medicine and engineering, to help them conduct research ...

Physicists design zero-friction quantum engine

Sep 16, 2014

(Phys.org) —In real physical processes, some energy is always lost any time work is produced. The lost energy almost always occurs due to friction, especially in processes that involve mechanical motion. ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Callippo
not rated yet Sep 19, 2011
The graphene's light absorbtion enables to measure fine structure constant directly.

http://www.condma...8fsc.pdf

But I don't think, it will improve the kilogram definition, which depends on the vacuum density, which can change with presence of cold neutrinos and axions in rather uncontrollable way.

http://www.physor...759.html

http://www.physor...s64.html

http://arxiv.org/abs/0908.0249

http://www.nature...30a.html