I was wondering that does the momentum (direction also) of emitted electron depend on absurbed photon or not? I couldn't find much explanation on internet about it. They show like the emission of electron occurs in random direction.
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$\begingroup$ I think you could guess that using the conservation of momentum! $\endgroup$– rnels12Commented Jul 26, 2019 at 11:09
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It is not completely random. Most of the direction of the distribution of the ejected electrons will go in the direction of polarization of the incident light, if it is linearly polarized.
https://en.wikipedia.org/wiki/Photoelectric_effect
https://journals.aps.org/pr/abstract/10.1103/PhysRev.23.137
Now most of the photoelectrons are ejected in the same direction as the incident direction of the photons.
Your reasoning is quite correct, and you can see exactly this phenomenon in a photomultiplier tube. The photomutiplier tube uses very thin metal sheets, and when a photon strikes the sheet the primary photoelectron is emitted in the same direction as the incident photon and escapes from the far side of the sheet:
Why are photoelectrons emitted in the direction of incident photons?
answered Jul 26, 2019 at 11:19
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$\begingroup$ Thank you for your answer and papers you shared. This answers my question. $\endgroup$– MurataniCommented Jul 26, 2019 at 11:45
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$\begingroup$ Would the following make up some other question: What about the elastic scattering of photons (in a mirror)? The direction is not random at all. Is there an exchange of momentum or energy. From the perspective of the question here: Doesn't "conservation of momentum" (see comment to question) imply that there cannot be random direction of emission? $\endgroup$ Commented Nov 16, 2022 at 15:55