Heterostructure Lasers, Part B: Materials and Operating Characteristics focuses on the operating characteristics of heterostructure lasers and the semiconductor materials used to fabricate them. Each major topic is introduced along with the basic laws that govern the observed phenomena. The expressions relevant to heterostructure lasers are derived from the basic laws, and realistic numerical examples based on the GaAs-AlxGa1-xAs heterostructure are given. This book is comprised of four chapters and begins with a discussion on semiconductor materials that have been used most extensively to fabricate heterostructure injection lasers, particularly combinations of III-V compounds. IV-VI binary compounds and their solutions are described, along with compositional grading for heterostructure lasers. The next chapter presents the phase equilibria, impurity incorporation, and the epitaxial growth techniques for heterostructure lasers, namely, liquid-phase epitaxy, molecular-beam epitaxy, and chemical vapor deposition. The fabrication and operating characteristics of both broad-area and stripe-geometry heterostructure lasers are then examined. The final chapter is devoted to the degradation of heterostructure lasers, with emphasis on catastrophic mirror damage at high power densities, "dark-line defect" formation, and gradual degradation. This monograph will be of interest to physicists.