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Measure direction of subpicoamp current

  1. Jun 20, 2013 #1
    Is it possible to measure the direction of a current at current magnitudes this small? Or only its magnitude?
  2. jcsd
  3. Jun 20, 2013 #2
    Measure using what method.
    It is possible to measure the direction of currents to ground in the femtoampere range.
  4. Jun 21, 2013 #3


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    There are many commerical instruments that can go well below a pA
    See e.g.

    This is from the point of view of the user no different than using a multimeter.

    Note that how well you can do this will depend on the impedance, it is possible to measure very small currents if you somehow can "translate" your current into a voltage via a (large) impedance (but there are limits to how this can be done, e.g. the Johnson noise of the impedance).
  5. Jun 21, 2013 #4

    jim hardy

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