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Title: Surface contact potential patches and Casimir force measurements

Abstract

We present calculations of contact potential surface patch effects that simplify previous treatments. It is shown that, because of the linearity of Laplace's equation, the presence of patch potentials does not affect an electrostatic calibration of a two-plate Casimir measurement apparatus. Using models that include long-range variations in the contact potential across the plate surfaces, a number of experimental observations can be reproduced and explained. For these models, numerical calculations show that if a voltage is applied between the plates which minimizes the force, a residual electrostatic force persists, and that the minimizing potential varies with distance. The residual force can be described by a fit to a simple two-parameter function involving the minimizing potential and its variation with distance. We show the origin of this residual force by use of a simple parallel capacitor model. Finally, the implications of a residual force that varies in a manner different from 1/d on the accuracy of previous Casimir measurements is discussed.

Authors:
; ;  [1];  [2]
  1. Yale University, Department of Physics, P.O. Box 208120, New Haven, Connecticut 06520-8120 (United States)
  2. Theoretical Division MS B213, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
21408221
Resource Type:
Journal Article
Journal Name:
Physical Review. A
Additional Journal Information:
Journal Volume: 81; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.81.022505; (c) 2010 The American Physical Society; Journal ID: ISSN 1050-2947
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ACCURACY; CALIBRATION; CAPACITORS; CASIMIR EFFECT; DISTANCE; ELECTRIC POTENTIAL; PLATES; POTENTIALS; SURFACES; VARIATIONS; ELECTRICAL EQUIPMENT; EQUIPMENT

Citation Formats

Kim, W J, Sushkov, A O, Lamoreaux, S K, and Dalvit, D A. R. Surface contact potential patches and Casimir force measurements. United States: N. p., 2010. Web. doi:10.1103/PHYSREVA.81.022505.
Kim, W J, Sushkov, A O, Lamoreaux, S K, & Dalvit, D A. R. Surface contact potential patches and Casimir force measurements. United States. https://doi.org/10.1103/PHYSREVA.81.022505
Kim, W J, Sushkov, A O, Lamoreaux, S K, and Dalvit, D A. R. Mon . "Surface contact potential patches and Casimir force measurements". United States. https://doi.org/10.1103/PHYSREVA.81.022505.
@article{osti_21408221,
title = {Surface contact potential patches and Casimir force measurements},
author = {Kim, W J and Sushkov, A O and Lamoreaux, S K and Dalvit, D A. R.},
abstractNote = {We present calculations of contact potential surface patch effects that simplify previous treatments. It is shown that, because of the linearity of Laplace's equation, the presence of patch potentials does not affect an electrostatic calibration of a two-plate Casimir measurement apparatus. Using models that include long-range variations in the contact potential across the plate surfaces, a number of experimental observations can be reproduced and explained. For these models, numerical calculations show that if a voltage is applied between the plates which minimizes the force, a residual electrostatic force persists, and that the minimizing potential varies with distance. The residual force can be described by a fit to a simple two-parameter function involving the minimizing potential and its variation with distance. We show the origin of this residual force by use of a simple parallel capacitor model. Finally, the implications of a residual force that varies in a manner different from 1/d on the accuracy of previous Casimir measurements is discussed.},
doi = {10.1103/PHYSREVA.81.022505},
url = {https://www.osti.gov/biblio/21408221}, journal = {Physical Review. A},
issn = {1050-2947},
number = 2,
volume = 81,
place = {United States},
year = {2010},
month = {2}
}