Featured Research

from universities, journals, and other organizations

New Research Expected To Improve Laser Devices And Make Photovoltaics More Efficient

Date:
November 14, 2008
Source:
University of Chicago
Summary:
Scientists have induced electrons in the nanocrystals of semiconductors to cool more slowly by forcing them into a smaller volume. This has the potential to improve satellite communications and the generation of solar power. Slowing down the cooling of these electrons -- in this case, by more than 30 times -- could lead to a better infrared laser source and increase the bandwidth of communication satellites. It also could lead to more efficient photovoltaic devices.

University of Chicago scientists have induced electrons in the nanocrystals of semiconductors to cool more slowly by forcing them into a smaller volume. This has the potential to improve satellite communications and the generation of solar power.

"Slowing down the cooling of these electrons—in this case, by more than 30 times—could lead to a better infrared laser source," said Philippe Guyot-Sionnest, Professor of Chemistry and Physics at the University of Chicago. "This, in turn, could be used to increase the bandwidth of communication satellites, allowing for faster connections."

Guyot-Sionnest is the principal investigator on the research project, which was described in a paper called "Slow Electron Cooling in Colloidal Quantum Dots," published Nov. 7 in Science.

The slow cooling of electrons in nanocrystals could lead to better, more efficient photovoltaic devices, he added. "This is because proposals to devise ways to extract the excess heat from these electrons as they cool are more likely to be realized—and to work—due to the fact that we now understand better what is going on with these nanocrystals."

Slower cooling of electrons in nanocrystals was first theorized in 1990, but no one has been able to observe this effect.

Slow electron cooling in nanocrystals occurs because forcing the electrons into a smaller volume leads them to oscillate between their alternate extremes within a very short period of time. (This is analogous to the way shorter strings on musical instruments produce higher pitches.) The electrons in the nanocrystals used in this experiment oscillated so fast that it became difficult for them to drag along the more sluggish vibrations of the nuclei. As a result, the energy stayed with the electrons for a longer period of time.

The slower cooling effect was difficult to induce and observe because several different mechanisms for energy loss interfered with the process. By eliminating these other mechanisms, the researchers were able to induce and observe slower electron cooling in nanocrystals.

Anshu Pandey, a graduate student in Chemistry at the University of Chicago, did the experiments described in the Science paper, which he co-authored.


Story Source:

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


Cite This Page:

University of Chicago. "New Research Expected To Improve Laser Devices And Make Photovoltaics More Efficient." ScienceDaily. ScienceDaily, 14 November 2008. <www.sciencedaily.com/releases/2008/11/081113111225.htm>.
University of Chicago. (2008, November 14). New Research Expected To Improve Laser Devices And Make Photovoltaics More Efficient. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2008/11/081113111225.htm
University of Chicago. "New Research Expected To Improve Laser Devices And Make Photovoltaics More Efficient." ScienceDaily. www.sciencedaily.com/releases/2008/11/081113111225.htm (accessed April 16, 2014).

Share This



More Matter & Energy News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Google Patents Contact Lens Cameras; Internet Is Wary

Google Patents Contact Lens Cameras; Internet Is Wary

Newsy (Apr. 15, 2014) Google has filed for a patent to develop contact lenses capable of taking photos. The company describes possible benefits to blind people. Video provided by Newsy
Powered by NewsLook.com
The Walking, Talking Oil-Drigging Rig

The Walking, Talking Oil-Drigging Rig

Reuters - Business Video Online (Apr. 15, 2014) Pennsylvania-based Schramm is incorporating modern technology in its next generation oil-drigging rigs, making them smaller, safer and smarter. Ernest Scheyder reports. Video provided by Reuters
Powered by NewsLook.com
Dutch Highway Introduces Glow-In-The-Dark Paint

Dutch Highway Introduces Glow-In-The-Dark Paint

Newsy (Apr. 14, 2014) A Dutch highway has become the first lit by glow-in-the-dark paint — a project aimed at reducing street light use. Video provided by Newsy
Powered by NewsLook.com
Google Buys Drone Maker, Hopes to Connect Rural World

Google Buys Drone Maker, Hopes to Connect Rural World

Newsy (Apr. 14, 2014) Formerly courted by Facebook, Titan Aerospace will become a part of Google's quest to blanket the world in Internet connectivity. Video provided by Newsy
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:
from the past week

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