Photons coming from atoms, when electron changes levels

AI Thread Summary
Electromagnetic waves are produced when a charge oscillates, as noted in a Yale professor's lecture. In LED diodes, when electrons transition from a higher to a lower energy state, they emit photons, a process known as electroluminescence. The emitted light's color is determined by the bandgap energy of the materials in the p-n junction. The discussion highlights a curiosity about the mechanics behind photon emission and suggests further exploration in more specialized physics forums. Understanding these concepts is essential for those studying electrical engineering.
Bassalisk
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Today I did the usual thinking, watched some courses online etc. and found out(or rather reminded myself) that the EM waves can be produced only when a charge oscillates.(or that's what the professor at Yale said)

But then I remembered LED diodes, and their ability to emit light. Electron goes from higher energy to lower energy state and produces a photon in process. Not until today I gave this a thought.

How come it emits a photon? Photon is a EM wave, it oscillates. So in order to emit a photon, it had to oscillate in the process?
Is this one of those answers "it just does that", "its the way it works" or is there more to it? Because all textbooks are going as deep as: change of energy: emit a photon.
 
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Bassalisk said:
But then I remembered LED diodes, and their ability to emit light. Electron goes from higher energy to lower energy state and produces a photon in process. How come it emits a photon?
This effect is called electroluminescence and the color of the light is determined by the bandgap energy of the materials that form the p-n junction. I'm not the kind of guy you want to guide you further down this rabbit hole, but at least now you know where it is. Btw, maybe you should try a more physics oriented subforum if you want to push this? Good luck.
 
gnurf said:
This effect is called electroluminescence and the color of the light is determined by the bandgap energy of the materials that form the p-n junction. I'm not the kind of guy you want to guide you further down this rabbit hole, but at least now you know where it is. Btw, maybe you should try a more physics oriented subforum if you want to push this? Good luck.

Yes i posted it now in physics. I am used to this forum, because i study EE :D Thanks for the help!
 
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