Navigation Links
U-M physicists create first atomic-scale map of quantum dots
Date:9/29/2009

ANN ARBOR, Mich.---University of Michigan physicists have created the first atomic-scale maps of quantum dots, a major step toward the goal of producing "designer dots" that can be tailored for specific applications.

Quantum dots---often called artificial atoms or nanoparticles---are tiny semiconductor crystals with wide-ranging potential applications in computing, photovoltaic cells, light-emitting devices and other technologies. Each dot is a well-ordered cluster of atoms, 10 to 50 atoms in diameter.

Engineers are gaining the ability to manipulate the atoms in quantum dots to control their properties and behavior, through a process called directed assembly. But progress has been slowed, until now, by the lack of atomic-scale information about the structure and chemical makeup of quantum dots.

The new atomic-scale maps will help fill that knowledge gap, clearing the path to more rapid progress in the field of quantum-dot directed assembly, said Roy Clarke, U-M professor of physics and corresponding author of a paper on the topic published online Sept. 27 in the journal Nature Nanotechnology.

Lead author of the paper is Divine Kumah of the U-M's Applied Physics Program, who conducted the research for his doctoral dissertation.

"I liken it to exploration in the olden days," Clarke said of dot mapping. "You find a new continent and initially all you see is the vague outline of something through the mist. Then you land on it and go into the interior and really map it out, square inch by square inch.

"Researchers have been able to chart the outline of these quantum dots for quite a while. But this is the first time that anybody has been able to map them at the atomic level, to go in and see where the atoms are positioned, as well as their chemical composition. It's a very significant breakthrough."

To create the maps, Clarke's team illuminated the dots with a brilliant X-ray photon beam at Argonne National Laboratory's Advanced Photon Source. The beam acts like an X-ray microscope to reveal details about the quantum dot's structure. Because X-rays have very short wavelengths, they can be used to create super-high-resolution maps.

"We're measuring the position and the chemical makeup of individual pieces of a quantum dot at a resolution of one-hundredth of a nanometer," Clarke said. "So it's incredibly high resolution."

A nanometer is one-billionth of a meter.

The availability of atomic-scale maps will quicken progress in the field of directed assembly. That, in turn, will lead to new technologies based on quantum dots. The dots have already been used to make highly efficient lasers and sensors, and they might help make quantum computers a reality, Clarke said.

"Atomic-scale mapping provides information that is essential if you're going to have controlled fabrication of quantum dots," Clarke said. "To make dots with a specific set of characteristics or a certain behavior, you have to know where everything is, so that you can place the atoms optimally. Knowing what you've got is the most important thing of all."


'/>"/>

Contact: Jim Erickson
ericksn@umich.edu
734-647-1842
University of Michigan
Source:Eurekalert  

Related biology technology :

1. Physicists at UC Santa Barbara make discovery in quantum mechanics
2. NYU physicists find way to explore microscopic systems through holographic video
3. Nanophysicists find unexpected magnetic effect
4. Physicists discover important step for making light crystals
5. U of T physicists squeeze light to quantum limit
6. McGill physicists find a new state of matter in a transistor
7. Physicists tweak quantum force, reducing barrier to tiny devices
8. UBC physicists develop impossible technique to study and develop superconductors
9. Discovery by UC Riverside physicists could enable development of faster computers
10. New unifying theory of lasers advanced by physicists
11. Physicists saved from drowning in complexities of wetting theory
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
U-M physicists create first atomic-scale map of quantum dots
(Date:2/10/2016)...  Matchbook, Inc., a company specializing in procurement ... announced today the appointment of Jim Shuman ... nearly 25 years of experience in supply chain, ... two decades in executive level roles as the ... and, most recently headed global logistics and procurement ...
(Date:2/10/2016)... (PRWEB) , ... February 10, 2016 , ... ... expansion to their comprehensive training and support program, Sonalink™ remote monitoring. The inaugural ... procedures performed on Friday, February 5th, connecting Dr. Samuel Peretsman to a HIFU ...
(Date:2/10/2016)... Jolla CA (PRWEB) , ... February 10, 2016 , ... ... new agents for the treatment of Alzheimer’s disease, announced today it has been selected ... February 18th at the Breakers in Palm Beach, Florida. The purpose of the ...
(Date:2/9/2016)... ... February 08, 2016 , ... ... Location: Baruch S. Blumberg Institute at the Pennsylvania Biotechnology Center of Bucks County, ... and The Commonwealth Medical College (TCMC) will hold an open house for participants ...
Breaking Biology Technology:
(Date:2/2/2016)... MOUNTAIN VIEW, Calif. , Feb. 2, 2016 ... diabetic retinopathy market, Frost & Sullivan recognizes US-based ... North America Frost & Sullivan Award for New ... technology provider in North America ... standard in the rapidly growing diabetic retinopathy market. ...
(Date:1/27/2016)... 2016  Rite Track, Inc. a leading semiconductor equipment ... Chester, Ohio announced today the acquisition of PLUS ... in Austin, Texas , will significantly ... modifications, installations and technical support offerings for TEL Track ... commented, "PLUS has provided world class service including refurbishment, ...
(Date:1/21/2016)... India , January 21, 2016 ... According to a new market research report "Emotion Detection ... and Others), Software Tools (Facial Expression, Voice Recognition ... Regions - Global forecast to 2020", published by ... is expected to reach USD 22.65 Billion by ...
Breaking Biology News(10 mins):