Observing electrons surfing waves of light on graphene

June 9, 2017, ICFO
Electrons and light are moving in concert along the graphene sheet. Credit: ICFO/ F. Vialla

Researchers have studied how light can be used to observe the quantum nature of an electronic material. They captured light in graphene and slowed it down to the speed of the material's electrons. Then electrons and light started to move in concert, manifesting their quantum nature at such large scale that it could observed with a special type of microscope.

The experiments were performed with ultra-high-quality . To excite and image the ultra-slow ripples of in the graphene (also called plasmons), the researchers used a special antenna for light that scans the surface at a distance of a few nanometers. With this near-field nanoscope, they saw that the light ripples on the graphene moved more than 300 times more slowly than light, dramatically diverging from what is suggested by classical physics laws.

The work has been published in Science by ICFO researchers Dr. Mark Lundeberg, Dr. Achim Woessner, led by ICREA Prof. at ICFO Frank Koppens, in collaboration with Prof. Hillenbrand from Nanogune, Prof. Polini from IIT and Prof. Hone from Columbia University.

In reference to the accomplished experiments, Prof. Koppens says, "Usually, it is very difficult to probe the quantum world, and to do so requires ; here we could observe it with light at room temperature."

This technique paves the way for exploring many new types quantum materials, including superconductors or topological materials that allow for quantum information processing with topological qubits. In addition, Prof. Hillenbrand states that "this could just be the beginning of a new era of near field nanoscopy."

Prof. Polini says, "This discovery may eventually lead to understanding in a truly microscopic fashion complex quantum phenomena that occur when matter is subject to ultra-low temperatures and very high magnetic fields, like the fractional quantum Hall effect."

Explore further: Graphene plasmons go ballistic

More information: Tuning quantum nonlocal effects in graphene plasmonics, Science (2017). DOI: 10.1126/science.aan2735

Related Stories

Graphene plasmons go ballistic

January 12, 2015

Squeezing light into tiny circuits and controlling its flow electrically is a holy grail that has become a realistic scenario thanks to the discovery of graphene. This tantalizing achievement is realized by exploiting so-called ...

Using graphene to create quantum bits

May 18, 2017

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits—or qubits—that are stable, meaning they are not much affected by changes in their environment. This normally needs ...

Recommended for you

Engineers produce smallest 3-D transistor yet

December 10, 2018

Researchers from MIT and the University of Colorado have fabricated a 3-D transistor that's less than half the size of today's smallest commercial models. To do so, they developed a novel microfabrication technique that modifies ...

New traffic rules in 'Graphene City'

December 6, 2018

In the drive to find new ways to extend electronics beyond the use of silicon, physicists are experimenting with other properties of electrons, beyond charge. In work published today (Dec 7) in the journal Science, a team ...

Artificial synapses made from nanowires

December 6, 2018

Scientists from Jülich together with colleagues from Aachen and Turin have produced a memristive element made from nanowires that functions in much the same way as a biological nerve cell. The component is able to save and ...


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.