The effect of active layer thickness on lateral waveguiding in narrow-stripe gain-guided AlGaAs DH laser diodes

It has been found that the thickness of the active layer has an important influence on the width of the far-field distribution parallel to the active layer of narrow-stripe AlGaAs lasers. Furthermore, for very thin active layers, thermal effects may show up as a result of internal temperature gradients. The influence of the laser output power has also been investigated. It is found that the far field distribution becomes narrower at higher output. All these effects can be quantitatively described as being due to an effective reduction of the anti-guiding parallel to the plane of the active layer.