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Potential Step (wave amplitude)

  1. Aug 14, 2012 #1
    1. If the incident wave is coming from LHS,
    what happens to the wave amplitude on the RHS when electron energy is equal V0?

    2. the wavevectors on both sides of the step are different (generally), is there an energy at which the have the same magnitude?

    thanks for any help..
  2. jcsd
  3. Aug 14, 2012 #2


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    Staff: Mentor

    The usual way to analyse this problem uses assumptions about the electrons which cannot be satisfied in reality (especially: electrons with a single, fixed energy). And here you have a case where you can see this flaw.
    If you have a free electron which "moves", it cannot have a single energy value, it has some distribution. The parts above V0 can (partially) go through, the other parts are reflected. If your electron does not "move", the question is ill-defined.

    With low energy, everything gets reflected, with high energy, nearly everything is transmitted. So somewhere in between, you have 1/2 on both sides.
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