Hot Dots (IMAGE)
Caption
SLAC and Stanford researchers have made the first atomic-scale observations of how nanocrystals known as quantum dots lose their light-producing efficiency when excited with intense light. Dots were excited with green light (top) or higher-energy purple light (bottom), and scientists watched them respond with an "electron camera," MeV-UED. When hit with green light, the dots relaxed, and excited pairs of electrons and holes converted virtually all of the incoming energy to light. But when hit with purple light, some of the energy was trapped on the surface of the dot; this distorted the arrangement of surrounding atoms and wasted energy as heat. The results have broad implications for developing future quantum and photonics technologies where light replaces electrons in computers and fluids in refrigerators.
Credit
B. Guzelturk et al., Nature Communications, 25 March 2021
Usage Restrictions
None
License
Licensed content