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Photo electric current

  1. Jan 16, 2010 #1
    what will be the effect on photoelectric current if the intensity and frequency of incident photons are increased simultaneously. ? Will the current remain almost same? if so , why?
     
  2. jcsd
  3. Jan 16, 2010 #2
    The photoelectric current (like in a vacuum photodiode) increases linearly with the intensity (for a particular color light).
    The photoelectric current is zero above a particular wavelength threshold (below a particular frequency threshold). Above the frequency threshold, the current increases slowly as the frequency is increased, depending on the characteristics of the photocathode.
    The photocurrent will increase if BOTH intensity and frequency are increased simultaneously, again depending on the characteristics of the photocathode. See spectral response characteristics on page 4 of
    http://sales.hamamatsu.com/assets/pdf/parts_R/LARGE_AREA_PMT_TPMH1286E05.pdf
    Bob S
     
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