Casimir Forces

Theory

"On the attraction between two perfectly conducting plates,"

H.B.G. Casimir, Proc. K. Ned. Akad. Wet. 51, 793 (1948)

Quantum fluctuations of electromagnetic field in the vacuum between leads to an attractive force between perfect mirrors

                      

"The Theory of Molecular Attractive Forces Between Solids,"

E.M. Lifshitz, Soviet Physics 2, 73 (1956),

 Generalizes the result by considering fluctuating current sources in the bodies.

Experiment

The era of high precision tests, made possible by advent of scanning microscopy:

 "Demonstration of the Casimir Force in the 0.6 to 6µm Range," (using a torsion pendulum)

S.K. Lamoreaux, Phys. Rev. Lett. 78, 5 (1997)

   

  "Precision Measurements of the Casimir Force from 0.1 to 0.9µm," (using atomic force microscopy)

U. Mohideen and A. Roy, Phys. Rev. Lett. 81, 4549 (1998) (offline)

   Many other groups ....

Technological applications

Important in microelectromechanical systems (MEMS): micron-scale metallic machines

  "Quantum Mechanical Actuation of Microelectromechanical Systems by the Casimir Force,"

 H. B. Chan, V. A. Aksyuk, R. N. Kleiman, D. J. Bishop, Federico Capasso, Science 291, 1941 (2001)

   

  Stiction due to the attractive Casimir force is a challenge to design and operation of MEMs.

 A scattering formalism can treat objects of different shapes and material properties.

 Repulsive Casimir forces, levitation?

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