Simple gain form of 1.5 µm multimode laser diode incorporating band filling and intrinsic gain saturation effects

The gain form of a 1.5 µm multimode laser diode was derived by phenomenologically adding an intrinsic gain saturation term to the linearized gain form described in our previous report. Although the proposed gain form was simple, it almost perfectly matched the complex laser diode gain in a direct transition model implicitly incorporating both band filling and intrinsic gain saturation effects. Using laser diode rate equations including the proposed gain form, the characteristic power spectrum of a gain-switched pulse from a 1.5 µm multimode laser diode was successfully simulated.