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Piezoelecric Crystals

  1. Jun 23, 2010 #1
    If a constant pressure is kept on a piezoelectric crystal, will it continue to generate an electric field?
     
  2. jcsd
  3. Jun 23, 2010 #2

    Andy Resnick

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  4. Jun 23, 2010 #3
    Actually, if you try this you will notice that the voltage drops back to zero quite quickly (seconds).
    This is because the crystal is not a perfect insulator, and because you must extract some current to measure the voltage.
     
  5. Jun 23, 2010 #4

    K^2

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    Yeah, when you deform a piezoelectric crystal, a voltage builds up. But that means that there is going to be a force acting on any free charges hanging around, which will try to rearrange themselves to cancel the voltage. So after a while the crystal should be neutral again.
     
  6. Jun 23, 2010 #5
    Thanks for the help :)
     
  7. Jun 23, 2010 #6
    You may be interested in Ferroelectric materials too. These have constant electric fields wihout the need to apply a stress.
     
  8. Jun 24, 2010 #7
    You don't say. I'll be off to read up on them right now. Thanks :)
     
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