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Electrostatic Background Forces due to Varying Contact Potentials in Casimir Experiments

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 نشر من قبل Steve K. Lamoreaux
 تاريخ النشر 2008
  مجال البحث فيزياء
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The existence of a monotonic distance dependent contact potential between two plates in a Casimir experiment leads to an additional electrostatic force that is significantly different from the case of a constant potential. Such a varying potential can arise if there is a uniform gradient in the work function or contact potential across a plate, as opposed to random microscopic fluctuations associated with patch potentials. A procedure to compensate for this force is described for the case of an experiment where the electrostatic force is minimized at each measurement distance by applying a voltage between the plates. It is noted that the minimizing voltage is not the contact potential.

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