Fundamentals of Optoelectronics [antikvár]

PREFACE The invention of the laser and the subsequent development of low-loss optical fibers started a revolution in the communications industry about 25 years ago. Fibers today are used not only for long-distance telecommunication, but for connecting switching stations in the local telephone company, delivering cable television signals to the neighborhoods in the cities, and connecting local area networks in medium- to large-size offices. As demand for information technology increases, the demand for large bandwidth communication links will increase, ensuring that optical fibers will be increasingly used in neighborhoods, homes, offices, and even instrumentation and automobiles. There are some major technological problems, and indecisions, inhibiting the next stage of fiber-optic implementation. For example, should information be sent using time division format (binary pulses), phase modulation (coherent communication), or wavelength modulation? Time division multiplexing requires a heavy investment in mode-locked lasers and extremely high-speed detectors and electronics. Wavelength division multiplexing requires high-performance wavelength selective filters and tunable sources which can be economically produced. Coherent detection requires accessible frequency standards in the infrared region. None of these technologies is impossible, but presently none of them are cheap to implement, either. UntO significant hardware breakthroughs occur, it is unlikely that we will see fibers connected to the home or office. This book is directed at the hardware aspects of optoelectronics. Six major topics are covered: 1) fundamental principles of electromagnetic theory; 2) optical waveguides; 3) coupling and numerical analysis of waveguides; 4) detectors and noise; 5) optical emission and lasers; and 6) modulators and sensors. The emphasis is slightly heavier into optical waveguides because advances in optical communication will be based on passive waveguide structures coupled with new materials and structures. The text, pitched at the senior/first-year-graduate course level, requires only a basic familiarity with electromagnetic waves, and the ability to solve differential equations with boundary conditions. Part 1 of the text explores the basis for optical propagation and establishes the use of the MKS system, discussing the wave equation and the properties of materials such as attenuation and dispersion. Some of the material is redundant with what students should have seen as juniors, but it has been my experience that very few students really walk away with a working knowledge of Maxwell's equations from their junior-level E&M courses. Part 2 explores the operation of optical waveguides. We start with planar slab waveguides, then systematically advance to more complicated structures, such as