Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

25.07.2017

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University (Germany) and the University of St Andrews (Scotland) used light-emitting and extremely stable transistors to reach strong light-matter coupling and create exciton-polaritons.


Artistic rendering of a light-emitting transistor with carbon nanotubes between two mirrors for electrical generation of polaritons.

Image credit: Dr Yuriy Zakharko, co-author

These particles may pave the way for new light sources, so-called electrically pumped polariton lasers, that could be manufactured with carbon nanotubes. These findings, published in "Nature Materials", are the result of a cooperation between Prof. Dr Jana Zaumseil (Heidelberg) and Prof. Dr Malte C. Gather (St Andrews).

In recent years, research on organic, carbon-based semiconductors for optoelectronic components has led to a variety of applications. Among them are light-emitting diodes for energy-efficient, high-resolution smartphone and TV screens.

Despite the rapid progress in this area, realising an electrically pumped laser from organic materials remains elusive. To get closer to this goal, researchers in Heidelberg and St Andrews are working on coupling light and matter in semiconducting carbon nanotubes – microscopically small, tube-shaped structures of carbon.

When photons (light) and excitons (matter) are made to exchange energy fast enough they form new quasi-particles, known as exciton-polaritons, that also emit light. Under certain conditions these emissions can take on the properties of laser light. Prof. Zaumseil explains that exciton-polaritons are currently investigated as a new way to generate laser-like light from organic materials and research in this area has increased significantly.

The team of researchers around Prof. Zaumseil and Prof. Gather previously showed that it is possible to form exciton-polaritons in semiconducting carbon nanotubes. But they used an external laser to stimulate the formation of the light-emitting quasi-particles.

In their current experiments, the researchers showed that it is possible to use electricity to generate these particles. To achieve this, they developed a light-emitting transistor with a dense layer to semiconducting carbon nanotubes that was embedded between two metallic mirrors.

Because of the extreme stability and high conductivity provided by the carbon nanotubes in this device, current densities and thus polariton densities were orders of magnitude above any previously reported values. Calculations by PhD student Arko Graf – one of the two lead authors of the study, show that the demonstration of an electrically pumped polariton laser is within realistic reach. As the emission of these light sources can be tuned across a wide range of the near-infrared spectrum, this work holds particular promise for applications in telecommunications.

Original publication:
A. Graf, M. Held, Y. Zakharko, L. Tropf, M.C. Gather and J. Zaumseil: Electrical pumping and tuning of exciton-polaritons in carbon nanotube microcavities. Nature Materials (published online 17 July 2017), doi: 10.1038/nmat4940

Contact:
Prof. Dr Jana Zaumseil
Institute of Physical Chemistry
Phone +49 6221 54-5065
zaumseil@uni-heidelberg.de

Communications and Marketing
Press Office, phone +49 6221 54-2311
presse@rektorat.uni-heidelberg.de

Weitere Informationen:

http://www.pci.uni-heidelberg.de/apc/zaumseil/index.html
http://gatherlab.wp.st-andrews.ac.uk

Marietta Fuhrmann-Koch | idw - Informationsdienst Wissenschaft

More articles from Physics and Astronomy:

nachricht UNH scientists help provide first-ever views of elusive energy explosion
16.11.2018 | University of New Hampshire

nachricht NASA keeps watch over space explosions
16.11.2018 | NASA/Goddard Space Flight Center

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>