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Undergrad Lab Experiment

  1. Jun 12, 2007 #1
    Hi Y'all,

    I would like to demonstrate electron tunneling in my Modern Physics lab class.

    Does anyone know of how to set such an experiment up?

    We have a lot of equipment and $$$ available, so that's not a problem.

    I don't want to ask the prof beforehand because he's kinda dumb.
  2. jcsd
  3. Jun 12, 2007 #2
    I can't think of anything that would be all flashy since this is higly microscopic. You could do it with a zerner diode.
  4. Jun 12, 2007 #3


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    Staff: Mentor

    You might consider doing "microwave tunneling" instead:


    You can google microwave tunneling to get more hits and info.

    As for electron tunneling, I think you'd need to have access to at least a basic (small) semiconductor fabrication lab in order to make something for a demo. Does your school have an experimental fab?
  5. Jun 12, 2007 #4
    Thank you very much for both of your replies.

    I have seen the "photon tunneling on your kitchen table". Someone else is doing that.

    Yes, we have access to a semiconductor fabrication lab! Just tell me what you have in mind and I can get it rolling!
  6. Jun 12, 2007 #5


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    Staff: Mentor

    Quiz question -- what common electronic components use electron tunelling in their funtion? (and which would be the simplest to fab?)
  7. Jun 12, 2007 #6
    The average answer seems to be "tunneling diode" but it is difficult to see how one could demonstrate tunneling with such a device - other than to point at it and say "there's tunnelin' in that thar device!" ;)
  8. Jun 12, 2007 #7
    A Mosfet can have electron tunelling but I think it was a bad thing that needed to be minimized.
  9. Jun 12, 2007 #8
    Do you have an oscilloscope?
    Build a Scanning Tunnelling Microscope.:eek:

    Here's how to do it for 100 bucks....well, OK, $150. (Yes, you can create atomic images....)


    Last edited: Jun 12, 2007
  10. Jun 12, 2007 #9


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    Staff: Mentor

    ....except in at least one very important application in electronics...

    If you could tunnel charge onto, say, a floating gate of a MOSFET, what practical use could that be.... ?
  11. Jun 12, 2007 #10
    Thanks, Creator - I will definitely check that out! I appreciate your help!:smile:

    (Amazing how many non-answers I get on these silly forums)
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