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Updated: Jun 8, 2026

Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Increased spatial frequency in interferential undulations of coupled cavity lasers
Abstract:
Increased spatial frequency is experimentally observed in the interferential light-output undulation of coupled cavity lasers that use a Fabry-Perot laser diode. The frequencies correspond to undulation periods of λ/4, λ/6, λ/8, and λ/10, which are extremely short compared with the normal period of λ/2. This increase is explained theoretically with a multiple-mode model in which one of the longitudinal modes of a coupled cavity laser with the lowest lasing threshold is selected as a lasing mode. This theoretical explanation is confirmed through experiments with a distributed feedback laser that shows a strong single-mode oscillation and yields light-output undulations with a spatial period of λ/2.
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