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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Electromagnetic coherence theory of laser resonator modes
Toni Saastamoinen1, Jari Turunen, Jani Tervo
1University of Joensuu, Department of Physics, FI-80101 Joensuu, Finland. toni.saastamoinen@joensuu.fi
Abstract:
A theory of open laser resonators is formulated within the framework of the electromagnetic coherence theory. It is shown that if only one Fox-Li mode contributes to the field at a given frequency, then the field at that frequency is necessarily completely coherent in view of the space-frequency counterpart of the recently introduced degree of coherence of electromagnetic fields [Opt. Express 11, 1137 (2003)]. It is also shown that the relation between the number of Fox-Li modes and the new degree of coherence is analogous to the relation established in the scalar theory of laser resonator modes. Difficulties that arise with the formerly introduced visibility-based definition of the electromagnetic degree of coherence are briefly discussed.
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