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Homework Help: Ultrashort Optical Pulses

  1. Sep 22, 2012 #1
    If an ultrashort optical pulse has a complex wavefunction with central frequency corresponding to a wavelength = 585 nm and a Gaussian envelope of RMS width of 6 femtoseconds, how can I calculate how many optical cycles are contained in the pulse width?

    2. Relevant equations

    3. The attempt at a solution
    Not too sure where to begin. I don't understand how a width can be measured in seconds. If it had been provided as a length, I would assume that one needs to simply divide that length by two times the wavelength to get the amount of cycles.
  2. jcsd
  3. Sep 22, 2012 #2
    When you say of something "in two minutes drive from here", you refer to a distance in terms of time.
  4. Sep 22, 2012 #3
    So then I suppose I can multiply it by the speed of light to get a distance, and then divide accordingly to get the answer?
  5. Sep 22, 2012 #4
    That sounds right. The only issue is that with this sort of duration one cannot really talk of a particular frequency, but I guess that's what the problem wants you to neglect.
  6. Sep 22, 2012 #5
    Sounds good. Thanks for the help.
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