Title :
Properties of Pump-Laser Modules Exposed to Polarization-Dependent and Wavelength-Selective Feedback From Fiber Bragg Gratings
Author :
Matuschek, Nicolai ; Pliska, Tomas ; Lichtenstein, Norbert
Author_Institution :
Bookham (Switzerland) AG, Zurich
fDate :
3/1/2008 12:00:00 AM
Abstract :
The performance of fiber Bragg grating (FBG) stabilized pump-laser modules is strongly influenced by changes of the state of polarization (SOP) arising from intrinsic and/or induced birefringence of the fiber. Birefringence changes the SOP as the light propagates back and forth between laser and FBG, which are separated by a distance of 1 to 2 m. As a result, the effective wavelength-selective feedback provided by the FBG varies accordingly. Based on the steady-state solution of a set of multimode rate equations we present a new model allowing us to calculate the output characteristics of a grating-stabilized pump-laser module as function of effective feedback. An effective-reflector approach is applied to describe the external cavity between the front mirror and the FBG on the module´s front side. The polarization- and wavelength-dependent effective feedback from the grating is taken into account by a feedback parameter in the equations for the effective reflector. We present an extended traveling-wave amplifier model for calculating the TE- and TM-polarized contributions to the power from all output ports of the module. Our model is verified by comparison of simulation results with experimental data for a typical FBG-stabilized pump-laser module. The output characteristics are analyzed as function of effective feedback for both the principal TE-polarization as well as the residual TM-polarization modes.
Keywords :
Bragg gratings; birefringence; laser feedback; laser stability; light polarisation; optical pumping; semiconductor lasers; travelling wave amplifiers; FBG; TE-polarization modes; TM-polarization modes; distance 1 m to 2 m; effective-reflector approach; external cavity; fiber Bragg gratings; front mirror; induced fiber birefringence; multimode rate equations; polarization-dependent effective feedback; pump-laser modules; traveling-wave amplifier model; wavelength-selective feedback; Birefringence; Bragg gratings; Equations; Fiber gratings; Fiber lasers; Laser feedback; Laser modes; Optical fiber polarization; Optical propagation; Output feedback; Fiber birefringence; fiber Bragg grating; fiber Bragg grating stabilization; optical feedback; optical fiber polarization; polarization; semiconductor laser stabilization; semiconductor lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2007.912456