Experimental Investigation of the Casimir Force beyond the ProximityForce Approximation
Abstract
The analysis of all Casimir force experiments using a sphereplate geometry requires the use of the proximityforce approximation (PFA) to relate the Casimir force between a sphere and a flat plate to the Casimir energy between two parallel plates. Because it has been difficult to assess the PFA's range of applicability theoretically, we have conducted an experimental search for corrections to the PFA by measuring the Casimir force and force gradient between a goldcoated plate and five goldcoated spheres with different radii using a microelectromechanical torsion oscillator. For separations z<300 nm, we find that the magnitude of the fractional deviation from the PFA in the force gradient measurement is, at the 95% confidence level, less than 0.4z/R, where R is the radius of the sphere.
 Authors:
 Physics Department, Wabash College, Crawfordsville, Indiana 47933 (United States)
 (United States)
 Department of Physics, Indiana UniversityPurdue University Indianapolis, Indianapolis, Indiana 46202 (United States)
 Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974 (United States)
 Department of Physics, Purdue University, West Lafayette, Indiana 47907 (United States)
 Publication Date:
 OSTI Identifier:
 20955406
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevLett.98.050403; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; CASIMIR EFFECT; GEOMETRY; GOLD; OSCILLATORS; PLATES; SPHERES; TORSION
Citation Formats
Krause, D. E., Department of Physics, Purdue University, West Lafayette, Indiana 47907, Decca, R. S., Lopez, D., and Fischbach, E. Experimental Investigation of the Casimir Force beyond the ProximityForce Approximation. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVLETT.98.050403.
Krause, D. E., Department of Physics, Purdue University, West Lafayette, Indiana 47907, Decca, R. S., Lopez, D., & Fischbach, E. Experimental Investigation of the Casimir Force beyond the ProximityForce Approximation. United States. doi:10.1103/PHYSREVLETT.98.050403.
Krause, D. E., Department of Physics, Purdue University, West Lafayette, Indiana 47907, Decca, R. S., Lopez, D., and Fischbach, E. Fri .
"Experimental Investigation of the Casimir Force beyond the ProximityForce Approximation". United States.
doi:10.1103/PHYSREVLETT.98.050403.
@article{osti_20955406,
title = {Experimental Investigation of the Casimir Force beyond the ProximityForce Approximation},
author = {Krause, D. E. and Department of Physics, Purdue University, West Lafayette, Indiana 47907 and Decca, R. S. and Lopez, D. and Fischbach, E.},
abstractNote = {The analysis of all Casimir force experiments using a sphereplate geometry requires the use of the proximityforce approximation (PFA) to relate the Casimir force between a sphere and a flat plate to the Casimir energy between two parallel plates. Because it has been difficult to assess the PFA's range of applicability theoretically, we have conducted an experimental search for corrections to the PFA by measuring the Casimir force and force gradient between a goldcoated plate and five goldcoated spheres with different radii using a microelectromechanical torsion oscillator. For separations z<300 nm, we find that the magnitude of the fractional deviation from the PFA in the force gradient measurement is, at the 95% confidence level, less than 0.4z/R, where R is the radius of the sphere.},
doi = {10.1103/PHYSREVLETT.98.050403},
journal = {Physical Review Letters},
number = 5,
volume = 98,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}

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