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I Intensity of a laser

  1. May 19, 2016 #1
    I recall hearing that if you have a sample of N molecules, then the output of a laser consisting of this sample has intensity proportional to N. I've been looking for such a derivation but cannot find one, and am wondering if this is still true. It seems somewhat intuitive but my intuition isn't always right. Any references/explanations would be greatly appreciated!
  2. jcsd
  3. May 19, 2016 #2


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    Am struggling to understand what you are talking about ... maybe others are as well, hence the lack of responses

    can you please expand on what you are referring to
    is it a situation of firing a laser at a sample of something and using the reflected / refracted laser light to determine the sample composition ?
    or something completely different .... please put you question into context :smile:

  4. May 20, 2016 #3
    I READ it as a question about a lasing sample. So if a mole of CO2 is in a laser, it has a certain efficiency, and a certain maximum output. And then 2 moles of CO2 would have twice as many photons produced. That certainly seems intuitively to make sense to me as well.
  5. May 20, 2016 #4
    Exactly. It seems very intuitive and I'm just wondering if there any particular sources confirming this is the case.
  6. May 21, 2016 #5


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    If you scroll part way down the page you will find part of an article and a graph showing the increase.
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