Directly modulated high power semiconductor optical amplifier

High power Semiconductor Optical Amplifiers (SOA) are used in optical systems such as Mode Locked Lasers (MLL) as gain medium, or in Master Oscillator Power Amplifiers (MOPA) when they are monolithically integrated with a DFB Laser. In both applications, the optical power at the input of the SOA is rather large (from 1 to few 10 ^th of mW) leading to gain saturation in the device. We present here an experimental study of the harmonic regime for a saturated high power SOA. The electro-optic parameters are measured and a model is proposed in two configurations: when the modulation is applied at the input or at the output of a two section high power SOA.