Solid-State, Dye, and Semiconductor Lasers

In this chapter, the most important types of lasers involving high density active media are considered, namely solid-state, dye and semiconductor lasers. The chapter concentrates on those examples that are in widest use and whose characteristics are representative of a whole class of lasers. The main emphasis here is on stressing the physical behavior of the laser and relating this behavior to the general concepts developed in the previous chapters. Some engineering details are also provided with the main aim again of helping to provide for a better physical insight into the behavior of the particular laser. To complete the picture, some data relating to laser performances (e.g., oscillating wavelength(s), output power or energy, wavelength tunability, etc.) are also included to help providing some indication of the laser’s applicability. For each laser, after some introductory comments, the following items are generally covered: (1) Relevant energy levels; (2) excitation mechanisms; (3) characteristics of the laser transition(s); (4) engineering details of the laser structure(s); (5) characteristics of the output beam; (6) applications.