A light bulb isnt very useful without a reliable on/off switch. The same holds true for quantum dots. These ultra tiny electronic nanostructures someday may serve as the ones and zeros used by a superfast quantum computer, but first physicists need to refine their ability to turn quantum dots "on" and "off."
In the June 23, 2003, on-line issue of Applied Physics Letters, researchers from the National Institute of Standards and Technology (NIST) and the National Renewal Energy Laboratory (NREL) take a step in the right direction. They report a way to measure accurately the amount of laser light needed to shift the electrons in a particular type of quantum dot between two discrete states, a low energy, ground state and a higher energy, excited state.
The strength of the interaction between quantum dots and electromagnetic waves like laser light is affectionately known in physical science circles as the "dipole moment." Loosely translated, its a number that tells you how easy the dots are to excite.
Fred McGehan | EurekAlert!
UNH scientists help provide first-ever views of elusive energy explosion
16.11.2018 | University of New Hampshire
NASA keeps watch over space explosions
16.11.2018 | NASA/Goddard Space Flight Center
Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.
Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...
Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.
Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
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06.11.2018 | Event News
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16.11.2018 | Health and Medicine
16.11.2018 | Life Sciences
16.11.2018 | Life Sciences