What the blank makes quantum dots blink?

Quantum dots are nanoparticles of semiconductor that can be tuned to glow in a rainbow of colors. Since their discovery in the 1980s, these remarkable nanoparticles have held out tantalizing prospects for all kinds of new technologies, ranging from paint-on lighting materials and solar cells to quantum computer chips, biological markers, and even lasers and communications technologies.

But there's a problem: Quantum dots often blink.

This "fluorescence intermittency," as scientists call it, has put a damper on many potential applications. Lasers and logic gates won't work very well with iffy light sources. Quantum dots can absorb specific colors of light, too, but using them to harvest sunlight in photovoltaics is not yet very efficient, due in part to the mechanisms behind blinking.

University of Chicago scientists computing at the Department of Energy's National Energy Research Scientific Computing Center (NERSC) recently probed the mysterious blinking process in silicon quantum dots using simulations. Their results, published in the February 28 issue of Nanoscale, bring scientists a step closer to understanding -- and possibly remediating -- the problem.
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