Navigation Links
Argonne researcher studies what makes quantum dots blink
Date:10/5/2007

In order to learn more about the origins of quantum dot blinking, researchers from the U.S. Department of Energy's Argonne National Laboratory, the University of Chicago and the California Institute of Technology have developed a method to characterize it on faster time scales than have previously been accessed.

Nanocrystals of semiconductor material, also known as quantum dots, are being intensively investigated for applications such as light-emitting diodes, solid-state lighting, lasers, and solar cells. They are also already being applied as fluorescent labels for biological imaging, providing several advantages over the molecular dyes typically used, including a wider range of emitted colors and much greater stability.

Quantum dots have great promise as light-emitting materials, because the wavelength, or color, of light that the quantum dots give off can be very widely tuned simply by changing the size of the nanoparticles. If a single dot is observed under a microscope, it can be seen to randomly switch between bright and dark states. This flickering, or blinking, behavior has been widely studied, and it has been found that a single dot can blink off for times that can vary between microseconds and several minutes. The causes of the blinking, though, remain the subject of intense study.

The methods developed by Matt Pelton of Argonne's Center for Nanoscale Materials and his team of collaborators has revealed a previously unobserved change in the blinking behavior on time scales less than a few microseconds. This observation is consistent with the predictions of a model for quantum-dot blinking previously developed by Nobel Laureate Rudolph Marcus, contributor to this research, and his co-workers. In this model, the blinking is controlled by the random fluctuation of energy levels in the quantum dot relative to the energies of trap states on the surface of the nanocrystal or in the nearby environment.

The results of this research provide new insight into the mechanism of quantum-dot blinking, and should help in the development of methods to control and suppress blinking. Detailed results of this work have been published in a paper in the Proceedings of the National Academy of Sciences.


'/>"/>

Contact: Sylvia Carson
scarson@anl.gov
630-252-5510
DOE/Argonne National Laboratory
Source:Eurekalert

Related biology technology :

1. NimbleGen researcher to lead $415K DNA project
2. Tapping hidden assets: Wisconsin researchers who can create jobs
3. Genomics researcher Hood joins NimbleGen board
4. Researcher wants to commercialize adult stem cell discovery
5. National Academies induct five UW researchers
6. Wisconsin researchers defend stem cell company
7. Departure of nanotech researcher stings UW
8. Medical College researcher working to make genetic-based medicine a reality
9. NimbleGen partners with leading researchers
10. Medical College researchers win federal grants
11. Researchers say scientific reporting needs more perspective, less hype
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/23/2017)... , March 23, 2017  GlobeImmune, Inc. today announced ... the sale of 12,835,490 shares of its common stock ... of companies. In connection with the sale of its common ... cash and issue to GlobeImmune 200,000 shares, an estimated ... "We are pleased to enter into this ...
(Date:3/23/2017)... March 23, 2017 According to a report ... derivatives market is fragmented due to the presence of a large pool ... Thermo Fisher , and Sigma-Aldrich, compete with each other in ... collectively, held more than 76% of this market in 2016.  ... As of now, a ...
(Date:3/22/2017)... ... March 22, 2017 , ... ... tissue regeneration from small lab samples to full-size tissues, bones, even whole organs ... a vascular system that delivers blood deep into the developing tissue. , ...
(Date:3/22/2017)...   iSpecimen ®, the marketplace for ... Service (DPS), a full-service anatomic pathology reference lab ... States , has joined a program offered by ... (DHIN) to make human biospecimens and associated data available ... announced in 2015 as a collaboration between iSpecimen and ...
Breaking Biology Technology:
(Date:2/13/2017)... , Feb. 13, 2017  RSA Conference -- ... platform that is designed to enhance fraud detection ... release in the RSA Fraud & Risk Intelligence ... organizations to leverage additional insights from internal and ... to better protect their customers from targeted cybercrime ...
(Date:2/10/2017)... -- Research and Markets has announced the ... Scientific and Commercial Aspects" to their offering. ... Biomarkers play ... therapy for selection of treatment as well for monitoring the ... disease in modern medicine. Biochip/microarray technologies and next generation sequencing ...
(Date:2/8/2017)... 8, 2017 About Voice Recognition Biometrics Voice ... it against a stored voiceprint template. Acoustic features ... and tone are compared to distinguish between individual ... as most PCs already have a microphone and ... recognition biometrics are most likely to be deployed ...
Breaking Biology News(10 mins):