Polarization dependent a-factor in InGaAs/InGaAsP MQW material

Multiple Quantum Well (MQW) structures are of high interest for many types of op tical devices because of the improved performance. Material parameters such as the linewidth enhancement factor (or-factor) [1] and the related differential gain (dg/dN) and differential refractive index (dn/dN) are essential in the design of lasers and optical amplifiers, because they govern important properties as linewidth, frequency response and resonance frequency. So far, most of the characterization has been carried out for the TE-polarization, but the polarization dependence of these parameters is important to the optimization of the MQW structures. Here we present measurements of the polarization dependence of dn/dN, dg/dN and the or-factor in a MQW amplifier. Theoretical results are also presented and reasonable agreement with measured data is obtained.