Optical Transmitters

The main elements of a laser, in particular of a semiconductor laser, are described. The active element, the semiconductor, is explained in detail. The lattice structure of crystalline semiconductors and the role of dimension (0D to 3D) are described. Recombination processes and their importance for LED and semiconductor lasers are explained. Basic structures such as double-hetero-diode (DHD) and multi-quantum-well (MQW) structures as well as special features of the resonator structure in semiconductor lasers (Fabry-Perot lasers, dynamic single-mode lasers) are presented. Important laser properties such as P-I characteristics, spectrum, and radiation characteristics are explained. Finally, selected laser types for optical networks are presented.