Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Short-Range Scattering in Quantum Dots Discovery Advances Novel Devices

21.10.2010
Chinese researchers, reporting in the Journal of Applied Physics, published by the American Institute of Physics, have described a new breakthrough in understanding the way electrons travel around quantum dots. This might lead to promising new fabrication methods of novel quantum devices.

Guodong Li and colleagues at the National Center for Nanoscience and Technology in Beijing carried out an experiment using self-assembled quantum dots and a two-dimensional electron gas, and then fit the data to a model to find out the type of scattering exhibited.

Much recent work has examined the internal structure of electron states of these 10-nm-scale quantum dots, which are tiny, very efficient energy absorbers that can release energy at custom frequencies depending on their size. Self-assembled quantum dots hold great promise for inexpensive fabrication of all kinds of novel applications such as lasers, detectors, and optical data storage, as well as in nanotechnology research.

What is missing, says the team, is an understanding of the scattering effects of the electrons. Optimizing scattering may be useful as a way of efficiently transporting electrons and thereby maximizing the performance of quantum dot-based devices.

To study these effects, the researchers placed an AlGaAs/GaAs two-dimensional electron gas (2DEG) near embedded GaSb/GaAs type-II quantum dots at a temperature of 4.2 K.

"The type-II GaSb quantum dots only confine the holes and not the electrons," says coauthor Chao Jiang, "so they are free to interact with the 2DEG."

Measurements at various voltages in the coupled system showed that the scattering mechanism is short-range, an idea verified by a simple model with a constant scattering potential.

"For the first time, we have clarified that the mechanism of electron scattering in this type of quantum dot system is short-range," says Chao. "The result is particularly significant for the future designing of very efficient quantum-dot-based devices."

The article, "Short Range Scattering Mechanism of Type-II GaSb/GaAs Quantum Dots on the Transport Properties of Two-dimensional Electron Gas" by Chao Jiang, Guodong Li, Hong Yin (National Center for Nanoscience and Technology, China), Qinsheng Zhu (Chinese Academy of Science) and Hiroyuki Sakaki (Toyota Technological Institute) appears in the Journal of Applied Physics. http://link.aip.org/link/japiau/v108/i4/p043702/s1

Journalists may request a free PDF of this article by contacting jbardi@aip.org

ABOUT JOURNAL OF APPLIED PHYSICS
Journal of Applied Physics is the American Institute of Physics' (AIP) archival journal for significant new results in applied physics; content is published online daily, collected into two online and printed issues per month (24 issues per year). The journal publishes articles that emphasize understanding of the physics underlying modern technology, but distinguished from technology on the one side and pure physics on the other. See: http://jap.aip.org/
ABOUT AIP
The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.

Jason Socrates Bardi | Newswise Science News
Further information:
http://www.aip.org

More articles from Physics and Astronomy:

nachricht Unconventional superconductor may be used to create quantum computers of the future
19.02.2018 | Chalmers University of Technology

nachricht Hubble sees Neptune's mysterious shrinking storm
16.02.2018 | 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: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Contacting the molecular world through graphene nanoribbons

19.02.2018 | Materials Sciences

When Proteins Shake Hands

19.02.2018 | Materials Sciences

Cells communicate in a dynamic code

19.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>