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Stanley514
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A new spintronic LED was invented by Utah physicists.
http://unews.utah.edu/news_releases/utah-physicists-invent-spintronic-led/
I thought that electron and hole suppose to recombine if electron is in exited state which means electron-hole pair is not in thermodynamic equilibrium with host material. But if carriers just injected in material, why they suppose to recombine? Does that mean that this new material becomes charged after recombination?
The second advance was the use of an extremely thin layer of lithium fluoride deposited on the cobalt electrode. This layer allows negatively charged electrons to be injected through one side of the spin valve at the same time as positively charged electron holes are injected through the opposite side. That makes the spin valve “bipolar,” unlike older spin valves, into which only holes could be injected.
It is the ability to inject electrons and holes at the same time that allows light to be generated. When an electron combines with a hole, the two cancel each other out and energy is released in the form of light.
http://unews.utah.edu/news_releases/utah-physicists-invent-spintronic-led/
I thought that electron and hole suppose to recombine if electron is in exited state which means electron-hole pair is not in thermodynamic equilibrium with host material. But if carriers just injected in material, why they suppose to recombine? Does that mean that this new material becomes charged after recombination?