- #1
Shailesh Pincha
- 17
- 0
How is a photon responsible for de-excitation of an electron in higher energy state?
Shailesh Pincha said:How is a photon responsible for de-excitation of an electron in higher energy state?
Shailesh Pincha said:Whatever i read doesn't satisfy the view that something like Stimulated emission really occurs.
Its just 1 of every 1000000 atoms where it occurs,as said, and that too when photon interacts with an excited electron without transfer of any sort of energy or momentum. Then how if photon responsible for electron's de-excitation. Further, if its just 1 of every 1000000 then it is possible that during the time, the photon is passing the atom the electron gets de-excites at the same moment by itself and we think it is photon who did it?
Shyan said:The sceou're describing is in fact spontaneous emission happening accidentally when a photon is passing by. That's OK but the point is spontaneous emission is considered before!
Physicists like to have theories as general as possible and resort to further assumptions only if things are very hard in the general case. Here it will be a further assumption if we say the electrons just ignore the fact that a photon is nearby. To keep things general, its said that the electron does not ignore the photon's presence. But how does it react? Absorbing the photon and going to an upper level is an obvious reaction. But here, people say:"Hey, what if the electron reacts by going down and emitting another photon? Let's have a theory with that stuff and see what are we going to get!". And the theory proved to be a good one: we have lasers! That's because no one has problem with stimulated emission:There is no reason not to consider it and its in agreement with observations!
Stimulated emission is a process in which an excited electron in an atom or molecule is de-excited by emitting a photon of the same frequency and phase as the incoming photon. This process is the basis for the operation of lasers.
Spontaneous emission occurs when an excited electron spontaneously emits a photon without any external influence. In stimulated emission, an external photon triggers the emission of another photon of the same frequency and phase, resulting in a cascade of emissions.
Stimulated emission is essential for the operation of lasers as it allows for the production of a coherent and intense beam of light. The emitted photons are all in phase and have the same frequency, resulting in a powerful and focused beam of light.
Population inversion is a state in which there are more excited electrons in an atom or molecule than there are in the ground state. This is necessary for stimulated emission to occur, as it requires an external photon to trigger the emission of another photon. Lasers achieve population inversion through an energy source, such as a pump laser or electrical discharge.
Stimulated emission can occur in any material that has energy levels that allow for the de-excitation of electrons with the emission of photons. However, not all materials are suitable for use in lasers, as they must also have the ability to achieve and maintain population inversion.