Title :
DFB laser with attached external intensity modulator
Author :
Marcuse, Dietrich
Author_Institution :
AT&T Bell Lab., Holmdel, NJ, USA
fDate :
2/1/1990 12:00:00 AM
Abstract :
A theoretical study is made of the frequency pulling effect exerted on a distributed feedback (DFB) laser by an external amplitude modulator that is directly attached to it. The modulator consists of a piece of waveguide whose loss is modulated by means of an externally applied voltage. The modulator affects the laser due to residual reflections from its far end which appear as a variable effective reflectivity to the output end of the DFB laser. Modulation affects the magnitude as well as the phase of the effective reflection coefficient presented to the laser due to the coupling of the real and imaginary parts of the effective refractive index of the modulator waveguide. The tuning problem is formulated as an eigenvalue equation for the DFB laser in the presence of an externally attached lossy cavity
Keywords :
distributed feedback lasers; eigenvalues and eigenfunctions; laser theory; laser tuning; optical losses; optical modulation; optical waveguides; reflectivity; refractive index; DFB laser; effective reflection coefficient; effective refractive index; eigenvalue equation; external amplitude modulator; external intensity modulator; externally applied voltage; externally attached lossy cavity; frequency pulling effect; modulator waveguide; output end; reflect coefficient magnitude; reflection coefficient phase; residual reflections; tuning problem; variable effective reflectivity; waveguide piece; Amplitude modulation; Distributed feedback devices; Frequency; Intensity modulation; Laser feedback; Laser theory; Laser tuning; Optical reflection; Phase modulation; Waveguide lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
