Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Controlling Electromagnetic Radiation by Graphene

27.11.2015

An international team of scientists from the University of Exeter, UK, Swiss Federal Institute of Technology in Zurich (ETHZ), Switzerland, and the University of Augsburg has demonstrated how the extraordinary properties of graphene can be exploited to create artificial structures that can be used to control and manipulate electromagnetic radiation over a wide range of wavelengths.

A collaborative international team consisting of two experimental groups, led by Professor Geoffrey Nash from the University of Exeter and Professor Jérôme Faist from the Swiss Federal Institute of Technology in Zurich, and of a theoretical group of Privatdozent Dr. Sergey Mikhailov from the University of Ausgburg, have engineered and investigated a remarkable new hybrid structure, or metamaterial, that possesses specific characteristics that are not found in natural materials.


A hybrid metamaterial structure designed in this work consists of an array of metallic (Au) split-ring resonators combined with graphene nano-ribbons placed between metallic elements.

© Isaac Luxmoore/University of Exeter

The team combined nano-ribbons of graphene together with a type of metallic antenna called a split ring resonator. Electrons in graphene are able to oscillate across the ribbon, performing so called plasma oscillations. Electrons in the metallic split-ring elements also oscillate with their own frequency.

These two types of oscillations interact with each other, with the interaction strength which can be controlled by the voltage applied between the graphene stripes and the back-side metallic contact. Careful design of these two elements leads to a system in which the hybrid plasma oscillations strongly interact with electromagnetic radiation.

As a result, the transmission of radiation through the structure can be controlled and manipulated by the electric voltage applied to it. The new structure can be thus used as a type of the terahertz-wave switch to interrupt, and turn on and off, a beam of this light very quickly.

The operation of this light modulator was demonstrated at the frequencies of several terahertz. The corresponding radiation wavelengths are very long, far beyond what the human eye can see. An important characteristic of the new structure is that it has the effect of focussing the electromagnetic radiation into an area much smaller than its wavelength. This could potentially lead to new ways of undertaking spectroscopic methods with ultra-high resolution.

The novel results obtained by the team could form the basis of a range of technologically important components. They are published in the respected scientific journal Nature Communications. This research work was carried out within the European FET Open Project GOSFEL ( www.gosfel.eu ), which aims to develop an entirely new laser source for many different applications in security, medicine, telecommunication, gas sensing, and so on. The Augsburg group also investigates nonlinear electrodynamic properties of graphene within another, large European research Program Graphene Flagship, with the goal to use them in different electronic and optoelectronic applications.

Publication:
Peter Q. Liu, Isaac J. Luxmoore, Sergey A. Mikhailov, Nadja A. Savostianova, Federico Valmorra, Jerome Faist, Geoffrey R. Nash, “Highly tunable hybrid metamaterials employing split-ring resonators strongly coupled to graphene surface plasmons”, Nature Communications 6, 8969 (2015).
http://www.nature.com/ncomms/2015/151120/ncomms9969/full/ncomms9969.html

Contact:
PD Dr. Sergey Mikhailov
Institut für Physik der Universität Augsburg
86135 Augsburg

Telefon +49(0)821-598-3255
sergey.mikhailov@physik.uni-augsburg.de
http://www.physik.uni-augsburg.de/lehrstuehle/theo2/team/mikhailov/

Weitere Informationen:

http://www.nature.com/ncomms/2015/151120/ncomms9969/full/ncomms9969.html
http://www.gosfel.eu
http://www.graphene-flagship.eu

Klaus P. Prem Presse | idw - Informationsdienst Wissenschaft

More articles from Materials Sciences:

nachricht Successful Mechanical Testing of Nanowires
07.12.2017 | Helmholtz-Zentrum Geesthacht - Zentrum für Material- und Küstenforschung

nachricht Nature's toughest substances decoded
05.12.2017 | Rice University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

Im Focus: A transistor of graphene nanoribbons

Transistors based on carbon nanostructures: what sounds like a futuristic dream could be reality in just a few years' time. An international research team working with Empa has now succeeded in producing nanotransistors from graphene ribbons that are only a few atoms wide, as reported in the current issue of the trade journal "Nature Communications."

Graphene ribbons that are only a few atoms wide, so-called graphene nanoribbons, have special electrical properties that make them promising candidates for the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

Blockchain is becoming more important in the energy market

05.12.2017 | Event News

 
Latest News

Making fuel out of thick air

08.12.2017 | Life Sciences

Rules for superconductivity mirrored in 'excitonic insulator'

08.12.2017 | Information Technology

Smartphone case offers blood glucose monitoring on the go

08.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>