Advances in Measurements of Physical Parameters of Semiconductor Lasers

We present a summary of the advances in characterization techniques allowing comprehensive study of physical processes in semiconductor lasers. The studies of the electrical characteristics and optical emission below threshold allow to measure the optical gain, linewidth enhancement factor, transparency wavelength, optical loss and carrier life-time. Some other parameters, such as leakage current and wavelength chirp, can only be deduced from the above threshold measurements. Measurements of the carrier temperature and carrier heating in semiconductor lasers allow to obtain important information about the devices performance at high injection current densities. Taken together, all these measurements provide critical experimental feedback in the laser design process. They also furnish essential information to guide our understanding of the microscopic physical processes determining the laser performance and our efforts to simulate those processes.