Modeling and measurement of spatial-hole-burning supplied to amplitude modulated coupling distributed feedback lasers

This work presents a theoretical and experimental study of the spatial hole burning (SHB) applied to phase-shifted amplitude modulated coupling (AMC) distributed feedback (DFB) lasers. Green's function method is used in our model and a new development of this method allows us to calculate the side-mode power. A transverse model is developed allowing the calculation of the spatially dependent refractive index and coupling coefficient from the designed AMC-DFB laser structures. Modeling results show that the effective index variation, associated with that of the coupling coefficient, plays an important role in affecting the laser's characteristics and has to be balanced to improve single-mode behavior. The SHB is studied experimentally by measuring the spontaneous emission radiated from a transparent window inside the electrode. The results clearly show, for the first time, the existence of a hole in the carrier density distribution due to the /spl lambda//4 phase-shift in a highly coupled laser. Both the measured and the calculated SHB are in agreement.<
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