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Double slit experiment with 2 detectors

  1. Jul 9, 2015 #1
    Can someone please point me to an experiment (photons/electrons/whatever) where detectors were placed on both slits, this seems like a really big hole in the experiment if they stopped at having just the one detector. (Excuse the pun)
     
  2. jcsd
  3. Jul 10, 2015 #2

    Nugatory

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    Here's one: https://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser#The_experiment_of_Kim_et_al._.282000.29

    It looks like a complicated way of doing something simple ("Just put a detector in each slot - how hard can that be?") but it has to be done that way because most detectors absorb the detected particle. If we just put a detector in each slit then nothing would get through and we wouldn't have any pattern at all.
     
  4. Jul 21, 2015 #3
    If the detector absorbs the wave then what's so strange about the interference pattern being destroyed? Wouldn't the absorption of the wave through 1 slit on the detector cause the the wave from the other slit to be out of phase and therefore not interfere?
     
  5. Jul 22, 2015 #4

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    Nothing's strange about not getting an interference pattern with only one slit open. What is strange is:
    1) The appearance of an interference pattern when both slits are open but we're using particles such as electrons, which classically weren't supposed to display any sort of wave behavior.
    2) The appearance of an interference pattern when both slits are open but we're sending the particles one at a time. That phenomenon has no classical explanation.
    3) The way the interference pattern goes away, even with both slits open, if we have a non-destructive detector operating at one or both slots. Your original question was asking for an example of sic an experiment, and Kim's apparatus is one such.
     
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