Measurement of linewidth enhancement factor in self-assembled quantum dot semiconductor lasers emitting at 1310 nm

Measurements of the linewidth enhancement factor (also termed the alpha-parameter) for quantum dot semiconductor lasers emitting at 1310 nm in both single and multiple transverse modes are presented. Values between 1.5 and 3.0 were measured depending on the device length. In addition, its spectral dependence within the inhomogeneously broadened ground and excited state is investigated.