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Light Illumination effect on metal conductivity

  1. Aug 27, 2010 #1
    How does shining light on a metal affect it's conductivity? Specifically, I'm wondering about IR light (1.5um) shining on either Aluminum or Gold.

    My intuition would say that if the metal isn't a perfect reflector and has some absorption, it would increase the number of carriers, thus increasing the conductivity, but I could be wrong.
  2. jcsd
  3. Aug 27, 2010 #2
  4. Aug 28, 2010 #3
    An increase in the number of carriers is what happens in engineered photosensitive devices (photodiodes).

    In metals, you won't increase the number of carriers. Afaik, 1.5 micron photons won't make electrons jump the bandgap in any common metal.

    The minor absorption will only cause a bit of heating, which might actually cause a very slight inrease in resistivity if anything.
  5. Aug 30, 2010 #4
    Thanks for the help. That answers my question.
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