Graphene mini-lab

October 31, 2012

A team of physicists from Europe and South Africa showed that electrons moving randomly in graphene can mimic the dynamics of particles such as cosmic rays, despite travelling at a fraction of their speed, in a paper about to be published in the European Physical Journal B.

Andrey Pototsky and colleagues made use of their knowledge of graphene, which is made of a carbon layer, one atom thick, and packed in a pattern. In such material the interaction of electrons with atoms changes the effective mass of the electrons. As a result, the energy of electrons in graphene becomes similar to the photon energy.

Therefore, electrons in graphene can be regarded as behaving like cosmic rays, which belong to a family known as ultra-, even though their actual velocity is one hundred times lower than the speed of light.

The authors employed the classical equations used to describe —so-called Brownian motion—to study the dynamics of electrons within the confines of their graphene mini-laboratory. They considered different graphene chip geometries and subjected them to changing conditions that affect the way these electrons diffuse through the material, such as temperature and electric field strength.

Going one step further, the authors were able to rectify electron fluctuations and to control the itself, from an unusual chaotic type of motion to a periodic movement, by varying the electric field.

Future work would experimentally demonstrate how variation of the temperature can be used positively to enhance the performance of graphene chips by gaining a greater control over . Such graphene mini-labs could also ultimately help us to understand the dynamics of matter and anti-matter in cosmic rays.

Explore further: Ultrafast imaging of electron waves in graphene (w/ Video)

More information: A. Pototsky, F. Marchesoni, F. V. Kusmartsev, P. Hanggi, and S. E. Savel'ev, Relativistic Brownian motion on a graphene chip, European Physical Journal B (2012) 85: 356, DOI: 10.1140/epjb/e2012-30716-7

Related Stories

Ultrafast imaging of electron waves in graphene (w/ Video)

November 10, 2010

The fastest "movies" ever made of electron motion have been captured by researchers using the U.S. Department of Energy’s Advanced Photon Source (APS) at Argonne and the Frederick Seitz Materials Research Laboratory ...

Two graphene layers may be better than one

April 27, 2011

(PhysOrg.com) -- Researchers at the National Institute of Standards and Technology have shown that the electronic properties of two layers of graphene vary on the nanometer scale. The surprising new results reveal that not ...

The secrets of tunneling through energy barriers

November 7, 2011

Electrons moving in graphene behave in an unusual way, as demonstrated by 2010 Nobel Prize laureates for physics Andre Geim and Konstantin Novoselov, who performed transport experiments on this one-carbon-atom-thick material. ...

New technique controls graphite to graphene transition

July 2, 2012

(Phys.org) -- University of Arkansas physicists have found a way to systematically study and control the transition of graphite, the “lead” found in pencils, to graphene, one of the strongest, lightest and most ...

Recommended for you

Neuromorphic computing mimics important brain feature

August 18, 2016

(Phys.org)—When you hear a sound, only some of the neurons in the auditory cortex of your brain are activated. This is because every auditory neuron is tuned to a certain range of sound, so that each neuron is more sensitive ...

'Artificial atom' created in graphene

August 22, 2016

In a tiny quantum prison, electrons behave quite differently as compared to their counterparts in free space. They can only occupy discrete energy levels, much like the electrons in an atom - for this reason, such electron ...

Picoscale precision though ultrathin film piezoelectricity

August 10, 2016

Piezoelectricity (aka the piezoelectric effect) occurs within certain materials – crystals (notably quartz), some ceramics, bone, DNA, and a number of proteins – when the application of mechanical stress or vibration ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.