Abstract

A fiber laser is phase modulated in the presence of a weak external reflection, leading to a strong intensity modulation at the laser output. The modulation causes the optical spectrum to be substantially more stable and smooth. The usefulness of the improved spectrum is illustrated by two different experiments, one for the characterization of an optical filter by measurement of its influence on the laser spectrum and the other for the measurement of the spatial-mode group-delay difference in a two-mode fiber by use of white-light interferometry. In both experiments the noise level is substantially reduced when the phase-modulated source is used.

© 1995 Optical Society of America

Multiplexed heterodyne fiber interferometer that uses laser-diode modulation

Ichirou Yamaguchi and Katsutoshi Hamano
Opt. Lett. 20(15) 1661-1663 (1995)

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A. P. Kovács, K. Osvay, Zs. Bor, and R. Szipöcs
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Effect of modulation instability on phase modulation–amplitude modulation conversion in optical fibers

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Single-pulse degenerate-cross-phase modulation in a single-mode optical fiber

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Spectral gain hole burning and modulation instability in a Brillouin fiber amplifier

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