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I Photoelectric effect in the study of a luminous diode (LED)

  1. Nov 5, 2018 #1
    I have studied the operation of light Diodes in the basic electronics course in my graduation and I had a question!
    Light Diodes (LEDs) are semiconductor materials with P-N junctions and that when energized emit visible light. I understand that the process of light emission when applying a source of energy is called electroluminescence. Thinking about the photoelectric effect, it is possible to make a relation of the emission of luminous photons, due to the process of recombination of electrons in the depletion regions of the P-N junction, with the photoelectric effect? Explaining my thinking, LED's of silicon and germanium, part of this energy due to recombination of gaps and electrons produce an energy in which most is released as heat, yet a small part is emitted almost negligibly is light. Knowing that the GAP energy in the silicon semiconductor is 1.1 eV, would it be possible for me to calculate the frequency of this light emission? Is this possible or am I commenting on a conceptual error in applying the photoelectric effect?

    Forgive my bad English, I recently started learning my language.
  2. jcsd
  3. Nov 5, 2018 #2


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    The "connection" between the LEDs and photoelectric effect is the ability to determine the Planck constant using the threshold current and voltage. This experiment is a common experiment, especially in high schools here in the US, because it doesn't require the more expensive setup involves in doing the photoelectric effect.


  4. Nov 5, 2018 #3
    Thanks for the clarification, the electronic address provided will be of great help for a project that I am idealizing.
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