We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK


93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Geometry, Sagnac ring lasers and twisted EM modes
View graph of relations

« Back

Geometry, Sagnac ring lasers and twisted EM modes

Research output: Contribution to journalJournal article


Journal publication date09/2005
JournalGeneral Relativity and Gravitation
Number of pages20
Original languageEnglish


A new geometric approximation scheme, designed to solve the covariant Maxwell equations inside a rotating hollow slender conducting cavity (modelling a ring-laser) on a background spacetime, is constructed. It is shown that for well-defined conditions the electromagnetic spectrum splits into TE- and TM-type modes. 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.

Bibliographic note

The original publication is available at www.springerlink.com