Open AccessThe instantaneous linewidth measurement of DFB laser with ultrashort delay
Author(s) -
Yi An,
Du Zhen-Hui,
Kexin Xu
Publication year - 2013
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.62.174208
Subject(s) - laser linewidth , laser , optics , phase noise , instantaneous phase , physics , injection seeder , beat (acoustics) , spectral density , phase (matter) , laser power scaling , materials science , computer science , telecommunications , radar , quantum mechanics
The instantaneous linewidth in the process of tuning is a very important parameter of laser, however only static linewidth in steady state could be obtained by all kinds of measurement at present. So we proposed a method of measuring instantaneous linewidth by time-frequency analysis based on local mean decomposition, and after its validity of extracting the instantaneous phase noise of simulation signal was proved, we set the heterodyne measurement system with ultrashort delay (about 0.5 ns) which came from 10 cm optical path difference. Finally, we not only extracted the time-frequency spectrum of the beat signal’s phase noise power, but also obtained the instantaneous linewidth of distributed-feedback diode laser under the pulse current for the first time so far as we Rnow.