Featured Research

from universities, journals, and other organizations

New material promises faster electronics

Date:
June 27, 2011
Source:
Vienna University of Technology, TU Vienna
Summary:
The novel material graphene makes faster electronics possible. Scientists have developed light detectors made of graphene and analyzed their astonishing properties.

High hopes are pinned on the new material: Graphene, a honeycomb-like carbon structure, made of only one layer of atoms, exhibits remarkable properties.
Credit: Copyright TU Wien

High hopes are pinned on the new material: Graphene, a honeycomb-like carbon structure, made of only one layer of atoms, exhibits remarkable properties. In 2010, the Nobel Prize was awarded for the discovery of graphene and its behavior. At the Photonics Institute at the TU Vienna, the electronic and optical properties of graphene are the focus of interest. Viennese scientists could now demonstrate how remarkably fast graphene converts light pulses into electrical signals. This could considerably improve date exchange between computers.

Converting Light into Electrical Signals

When data is transmitted by light pulses (for in stance in fiber optic cables) the pulses have to be converted back into electrical signals, which can be processed by a computer. This conversion of light into electrical current is possible due to the photoelectric effect, which was originally explained by Albert Einstein. In certain materials, light can cause electrons to leave their positions and travel through the material freely, whereby electrical current occurs. "Light detectors which convert light into electronic signals have been around for a long time. But when they are made of graphene, they react faster than most other materials could," Alexander Urich explains. He investigated the optical and electronic properties of graphene together with Thomas Mόller and Professor Karl Unterrainer at TU Vienna.

Analysis using Ultra Short Laser Pulses

The scientists had already shown last year that graphene can convert light into electronic signals with remarkable speed. However, the reaction time of the material could not be determined -- the photoelectric effect in graphene is so fast that it just cannot be measured by the usual measuring methods. But now, sophisticated technological tricks could shed some light on the properties of graphene. At TU Vienna, laser pulses were fired at the graphene photo-detector in quick succession, and the resulting photo-current was measured. If the time delay between the laser pulses is changed, the detector's maximum frequency can be determined. "Using this method we could show that our detectors can be used up to a frequency of 262 GHz," Thomas Mόller (TU Vienna) says. This corresponds to a theoretical upper bound for data transfer using graphene photo-detectors of more than 30 gigabytes per second. It has yet to be determined to what extent this is technically feasible, but this result clearly shows the remarkable capability of graphene and its potential for optoelectronic applications.

Fast Signals for Fast Electronics

The main reason for the fact that graphene-photodetectors can operate at such high frequencies is the short life-span of the charge carriers in graphene. The electrons which are removed from their fixed position and contribute to the electrical current settle down at another fixed position after a few picoseconds (millionths of a billionth of a second, 10E-12 seconds). As soon as this happens, the graphene photodetector is ready for another light signal which frees new electrons, creating the next electrical signal. The fast reaction time of graphene is one more item on the list of remarkable properties of this material. In graphene, charge carriers can travel extremely far without being disturbed. It can absorb light in a huge spectral range, from infrared to visible light -- unlike standard semiconductors, which can only absorb a small part of the spectrum. In addition to this, graphene can conduct heat extremely well and has an exceptionally high breaking strength.


Story Source:

The above story is based on materials provided by Vienna University of Technology, TU Vienna. Note: Materials may be edited for content and length.


Cite This Page:

Vienna University of Technology, TU Vienna. "New material promises faster electronics." ScienceDaily. ScienceDaily, 27 June 2011. <www.sciencedaily.com/releases/2011/06/110627095406.htm>.
Vienna University of Technology, TU Vienna. (2011, June 27). New material promises faster electronics. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2011/06/110627095406.htm
Vienna University of Technology, TU Vienna. "New material promises faster electronics." ScienceDaily. www.sciencedaily.com/releases/2011/06/110627095406.htm (accessed September 22, 2014).

Share This



More Matter & Energy News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Company Copies Keys From Photos

Company Copies Keys From Photos

Newsy (Sep. 22, 2014) — A new company allows customers to make copies of keys by simply uploading a couple of photos. But could it also be great for thieves? Video provided by Newsy
Powered by NewsLook.com
Rockefeller Oil Heirs Switching To Clean Energy

Rockefeller Oil Heirs Switching To Clean Energy

Newsy (Sep. 22, 2014) — The Rockefellers — heirs to an oil fortune that made the family name a symbol of American wealth — are switching from fossil fuels to clean energy. Video provided by Newsy
Powered by NewsLook.com
Raw: SpaceX Rocket Carries 3-D Printer to Space

Raw: SpaceX Rocket Carries 3-D Printer to Space

AP (Sep. 22, 2014) — A SpaceX Rocket launched from Cape Canaveral, carrying a custom-built 3-D printer into space. NASA envisions astronauts one day using the printer to make their own spare parts. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Inside London's Massive Sewer Tunnel Project

Inside London's Massive Sewer Tunnel Project

AP (Sep. 22, 2014) — Billions of dollars are being spent on a massive super sewer to take away London's vast output of waste, which is endangering the River Thames. (Sept. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins