Saturation effects in experiments on the thermal Casimir effect

Division of Theory and Modeling, Department of Physics, Chemistry and Biology, Linköping University SE-581 83 Linköping, Sweden, EU

Corresponding author: bos@ifm.liu.se

Received: 25 May 2009
Accepted: 29 June 2009

Abstract

We address three different problematic Casimir experiments in this work. The first is the classical Casimir force measured between two metal half-spaces; here in the form of the Casimir pressure measurement between a gold sphere and a gold plate as performed by Decca et al. (Phys. Rev. D, 75 (2007) 077101); theory predicts a large negative thermal correction, absent in the high-precision experiment. The second experiment is the measurement of the Casimir force between a metal plate and a laser irradiated semiconductor membrane as performed by Chen et al. (Phys. Rev. B, 76 (2007) 035338); the change in force with laser intensity is larger than predicted by theory. The third experiment is the measurement of the Casimir force between an atom and a wall in the form of the measurement by Obrecht et al. (Phys. Rev. Lett., 98 (2007) 063201) of the change in oscillation frequency of a ⁸⁷Rb Bose-Einstein condensate trapped to a fused silica wall; the change is smaller than predicted by theory. We show that saturation effects can explain the discrepancies between theory and experiment observed in all these cases.