Open AccessInstantaneous lineshape analysis of Fourier domain mode-locked lasers
Author(s) -
Sebastian Todor,
Benjamin R. Biedermann,
Wolfgang Wieser,
Robert Huber,
Christian Jirauschek
Publication year - 2011
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.008802
Subject(s) - laser linewidth , optics , laser , physics , mode locking , frequency modulation , time domain , frequency domain , bandwidth (computing) , semiconductor laser theory , fourier transform , spectral density , filter (signal processing) , amplified spontaneous emission , optical filter , telecommunications , computer science , quantum mechanics , computer vision
We present a theoretical and experimental analysis of the instantaneous lineshape of Fourier domain mode-locked (FDML) lasers, yielding good agreement. The simulations are performed employing a recently introduced model for FDML operation. Linewidths around 10 GHz are found, which is significantly below the sweep filter bandwidth. The effect of detuning between the sweep filter drive frequency and cavity roundtrip time is studied revealing features that cannot be resolved in the experiment, and shifting of the instantaneous power spectrum against the sweep filter center frequency is analyzed. We show that, in contrast to most other semiconductor based lasers, the instantaneous linewidth is governed neither by external noise sources nor by amplified spontaneous emission, but it is directly determined by the complex FDML dynamics.