Graphene lenses: 2-D electron shepherds

April 18, 2012

Researchers discover that a deformed layer of graphene can focus electrons similar to the way an optical lens bends light.

Graphene, the one-atom-thick "wonder material" made of carbon, has another potential use in the world of high-speed electronics – as a tool that can focus a stream of electrons similar to the way an focuses light. A new prototype reveals that a layer of graphene, when strained through stretching, can act as a two-dimensional lens for electrons. The research, which is published in the American Institute of Physics' (AIP) journal Applied Physics Letters, was produced by an international group of researchers from the Karlsruhe Institute of Technology in Germany and the French National Center for Scientific Research (CRNS).

Graphene is an excellent conductor: electrons flow freely across its surface in straight lines. According to a previously proposed theory, highly strained graphene impedes the flow of electrons, slowing them down and altering their trajectory. Scientists believed this effect could be used to focus electrons to a fine point – similar to the way an optical lens creates areas of refraction, or bending, to shepherd light to a point.

To create the prototype lens, the team of French and German researchers built a "deformed graphene carpet" that smoothly covers a series of hexagonal nano-holes in a silicon-carbide wafer. Areas of the graphene were strained as they adopted the shape of the holes in the wafer. The researchers found that they could control the focal length of a graphene lens by changing its geometry. Practical applications of this work include uses in high-speed electronics, where strained could act as a transport medium for information exchange between different parts of a circuit. Unlike traditional information exchange, in which electrons flow through cables whose paths cannot cross without a short, the new method would allow an unprecedented freedom of movement, similar to that of light in a vacuum.

Explore further: Two graphene layers may be better than one

More information: "A graphene electron lens" by Lukas Gerhard et al. is published in Applied Physics Letters.

Related Stories

Two graphene layers may be better than one

April 27, 2011

( -- 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 ...

Bilayer graphene is another step toward graphene electronics

August 11, 2011

The Nobel Prize winning scientists Professor Andre Geim and Professor Kostya Novoselov have taken a huge step forward in studying the wonder material graphene and revealing its exciting electronic properties for future electronic ...

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. ...

Flaky graphene makes reliable chemical sensors

January 17, 2012

Scientists from the University of Illinois at Urbana-Champaign and the company Dioxide Materials have demonstrated that randomly stacked graphene flakes can make an effective chemical sensor.

Recommended for you

A particle purely made of nuclear force

October 13, 2015

Scientists at TU Wien (Vienna) have calculated that the meson f0(1710) could be a very special particle – the long-sought-after glueball, a particle composed of pure force.

Light-optics research could improve medical imaging

October 13, 2015

A team of researchers, including The University of Queensland's Dr Joel Carpenter, has developed echo-less lights that could improve medical imaging inside the body, leading to less-intrusive surgery.

Just a touch of skyrmions

October 13, 2015

Ancient memory devices such as handwriting were based on mechanical energy—but in the modern world they have given way to devices based generally on electrical manipulation.


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.