This book represents a unique collection of the latest developments in the rapidly developing world of semiconductor laser diode technology and applications. An international group of distinguished contributors have covered particular aspects and the book includes optimization of semiconductor laser diode parameters for fascinating applications.
In 2009 the world celebrated 50 years of lasers, bringing to the attention of the
public how deeply lasers and laser related technologies have revolutionized both
science and everyday life. Next year will be the fiftieth anniversary of the semiconductor
laser. Used as a compact light source with high modulation rates, it
transformed telecommunications in combination with glass fibers. Today laser
diodes are omnipresent in data storage and communication. Still, most of these
applications are based on infrared or red laser diodes.
In this book, the performance characteristics of distributed feedback semiconductor laser diodes and optical tunable ﬁlters based on DFB laser structures have been investigated. As discussed in Chapter 1, these lasers can be used as optical sources and local oscillators in coherent optical communication networks, in which a stable single mode (in both the transverse plane and the longitudinal direction) and narrow spectral linewidth become crucial.
The introduction of semiconductor lasers has boosted the development of coherent optical communication systems. With the built-in wavelength selection mechanism, distributed feedback semiconductor laser diodes with a higher gain margin are superior to the Fabry– Perot laser in that a single longitudinal mode of lasing can be achieved. In this chapter, results obtained from the threshold analysis of conventional and singlephase-shifted DFB lasers will be investigated. In particular, structural impacts on the threshold characteristic will be discussed in a systematic way. ...
The above-threshold lasing characteristics of DFB semiconductor laser diodes were presented in the previous chapter using a modiﬁed transfer matrix. Instead of using an averaged carrier concentration, the inclusion of the actual carrier distribution allows phenomena such as the spatial hole burning effect and non-linear gain to be included. In the analysis, a parabolic gain model and high-order carrier recombination were assumed.
In the latest decade we have witnessed a tremendous advance in telecommunications
technology. With the rapid growth and sophistication of digital
technology and computers, communication systems have become more
versatile and powerful. This has given a modern communication engineer
two key problems to solve: (i) how to handle the ever-increasing demand for
capacity and speed in communication systems, and (ii) how to tackle the need
to integrate a wide range of computers and data sources so as to form a highly
integrated communication network with a global coverage....
The rapid development of both terrestrial and undersea optical ﬁbre networks has paved the way for a global communication network. Highly efﬁcient semiconductor injection lasers have played a leading role in facing the challenges of the information era. In this chapter, before discussing the operating principle of the semiconductor distributed feedback (DFB) laser diode (LD), general concepts with regard to the principles of lasers will ﬁrst be presented.
This book deals with theoretical and experimental aspects of solid-state lasers, including optimum waveguide design of end pumped and diode pumped lasers. Nonlinearity, including the nonlinear conversion, up frequency conversion and chirped pulse oscillators are discussed. Some new rare-earth-doped lasers, including double borate and halide crystals, and feedback in quantum dot semiconductor nanostructures are included.
Introduction to LEDs: How LEDs work + some points. Comparison with other sources of light. LED in communication. Blue &White LED technologies. How they are made? Their application? Brief about blue laser? Stands for light emitting diode.
emits incoherent narrow spectrum light
(due to recombination in transition region near the junction.)
Color of the emitted light depends on the chemical of the semiconducting material used.
(Near-ultraviolet, visible or infrared.)...
The role of the optical transmitter is to convert an electrical input signal into the corresponding optical signal and then launch it into the optical ﬁber serving as a communication channel. The major component of optical transmitters is an optical source. Fiber-optic communication systems often use semiconductor optical sources such as light-emitting diodes (LEDs) and semiconductor lasers because of several inherent advantages offered by them.
Free-standing semiconductor nanowires have been used to fabricate
nanometer-scale field-effect transistors (FETs), bipolar junction transistors, and light-
emitting diodes, nano-scale lasers, complementary inverters, complex logic gates, gas
sensors, nano-resonators, nano-generators and nano-photovoltaic devices. Since the very
first pioneering works carried out by K. Hiruma in Japan in the mid 90’s, and by C.M.