Phase Shifter Structure Research Articles

CW operation of a InGaAsP/InP gain-coupled distributed feedback laser with a corrugated active layer

A low-threshold continuous-wave (CW)-operable gain-coupled distributed-feedback laser with a corrugated active layer was realized with InGaAsP/InP materials by implementing active ion etching and organometallic vapor-phase epitaxy. Without any phase-shifting structures, the devices exhibited excellent single-longitudinal-mode oscillation, independent of facet reflection. Threshold currents as low as 12 mA and side-mode suppression ratios as high as 55 dB were demonstrated at a wavelength of 1.55 mu m.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Distributed feedback device characterization using a continuous wave model

The second-order cw equation for a medium having gain and a modulated index of refraction is solved to characterize an aperiodic distributed feedback structure. The solutions are compared with those of a coupled-wave model for the cases of tapered, chirped, and phase-shifted structures. A correlation is observed between the solutions, endorsing the validity of the cw approach.