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Question About the Photoelectric Effect for Lower Frequencies

  1. Jan 10, 2013 #1
    I'm going over the photoelectric effect and have run into a conceptual problem, and was hoping for some help in resolving it. In particular, I am looking at the frequencies below the threshold frequency of whatever metal is being examined.

    So, because of the lower frequency, there will be no photoelectrons. Where I am having trouble is with what happens to the energy of the photon that is still clearly interacting with the metal. The most that I could come up with is that an electron will go into an excited state, but will not have the energy to escape, and so, is pulled back.

    But if that is the case, isn't it possible that another photon could interact with the electron in this excited state, giving it the needed energy to escape? But I seem to be somehow going back to the classical view, because if that was the case, then the intensity would certainly help produce photoelectrons.

    Thank you!
  2. jcsd
  3. Jan 11, 2013 #2

    Simon Bridge

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    Yes. The excited electron decays so quickly that it is very unlikely that another photon will come along in time to eject it. The function of current vs intensity, below the cutoff frequency, is very different from that classically predicted ... and there isn't supposed to be a cutoff anyway.

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