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arXiv · 1307.2417

A novel scheme for hundred-hertz linewidth measurements with self-heterodyne method

Yu Peng
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Abstract

We propose a novel scheme for accurately determining hundred-hertz linewidth by delayed self-heterodyne method in which delay time far less than the laser's coherence time. That exceeds the former understanding as to the delayed self-heterodyne technique which requiring a prohibitively long fiber. The self-heterodyne autocorrelation function and power spectrum are evaluated and by numerical analysis we ensure that -3dB of power spectrum is applied to the self-heterodyne linewidth measurements. For laser linewidth less than 100 Hz, linewidth can be measured directly by 10 km fiber, and in more general case linewidth can be deduced from -20 dB or -40 dB of the fitting Lorentzian curve.

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Yu Peng. 2013-07-09. A novel scheme for hundred-hertz linewidth measurements with self-heterodyne method. https://doi.org/10.1088/0256-307x%2F30%2F8%2F084208

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