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arXiv · gr-qc/0411037

Twisted Electromagnetic Modes and Sagnac Ring-Lasers

David A. Burton·Adam Noble·Robin W. Tucker·David L. Wiltshire
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Abstract

A new approximation scheme, designed to solve the covariant Maxwell equations inside a rotating hollow slender conducting cavity (modelling a ring-laser), is constructed. It is shown that for well-defined conditions there exist TE and TM modes with respect to the longitudinal axis of the cavity. A twisted mode spectrum is found to depend on the integrated Frenet torsion of the cavity and this in turn may affect the Sagnac beat frequency induced by a non-zero rotation of the cavity. The analysis is motivated by attempts to use ring-lasers to measure terrestrial gravito-magnetism or the Lense-Thirring effect produced by the rotation of the Earth.

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David A. Burton, Adam Noble, Robin W. Tucker, David L. Wiltshire. 2004-11-08. Twisted Electromagnetic Modes and Sagnac Ring-Lasers. https://doi.org/10.1088/0264-9381%2F22%2F6%2F001

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