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Published on: December 18, 2015
Laser frequency modulation noise measurement by recirculating delayed self-heterodyne method
1Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Umezono, Tsukuba, Japan. h-tsuchida@aist.go.jp
Abstract:
I propose and demonstrate the use of the recirculating delayed self-heterodyne (DSH) method for measuring FM noise power spectral densities (PSDs), which are the most fundamental measure characterizing the spectral purity of laser sources. By analyzing the DSH beat signals with 1, 10, and 160 km delays, the FM noise PSD of a narrow-linewidth fiber laser is evaluated for Fourier frequency range between 10 Hz and 100 kHz, which exhibits flicker noise as the dominant contribution.

