Book contents
- Frontmatter
- Contents
- List of figures
- List of tables
- Preface
- Acknowledgments
- Partial list of symbols
- List of abbreviations
- Part I Background
- 1 General background
- Part II Waveguides and couplers
- Part III Nonlinear photonics
- Part IV Lasers
- Part V Semiconductor optoelectronics
- Appendix A Symbols and notations
- Appendix B Table of prerequisites
- Appendix C SI metric system
- Appendix D Fundamental physical constants
- Appendix E Fourier-transform relations
- Index
1 - General background
Published online by Cambridge University Press: 18 January 2010
- Frontmatter
- Contents
- List of figures
- List of tables
- Preface
- Acknowledgments
- Partial list of symbols
- List of abbreviations
- Part I Background
- 1 General background
- Part II Waveguides and couplers
- Part III Nonlinear photonics
- Part IV Lasers
- Part V Semiconductor optoelectronics
- Appendix A Symbols and notations
- Appendix B Table of prerequisites
- Appendix C SI metric system
- Appendix D Fundamental physical constants
- Appendix E Fourier-transform relations
- Index
Summary
Photonics is an engineering discipline concerning the control of light, or photons, for useful applications, much as electronics has to do with electrons. Light is electromagnetic radiation of frequencies in the range from 1 THz to 10 PHz, corresponding to wavelengths between∼300 μm and ∼30 nm in free space. This optical spectral range is generally divided into infrared, visible, and ultraviolet regions, as indicated in Table 1.1. The spectral range of concern in photonics is usually in a wavelength range between 10 μm and 100 nm. The primary interest in the applications of photonic devices is in an even narrower range of visible and near infrared wavelengths. As we shall see later, this spectral range of application is largely determined by the properties of materials used for photonic devices.
The wave nature of light is very important in the function of photonic devices. In particular, the propagation of light in a photonic device is completely characterized by its wave nature. However, in the spectral range of interest for practical photonic devices, the quantum energies of photons are in a range where the quantum nature of light is also important. For example, photons of visible light have energies between 1.7 and 3.1 eV, which are in the range of the bandgaps of most semiconductors. Photon energy is an important factor that determines the behavior of an optical wave in a semiconductor photonic device. The uniqueness of photonic devices is that both wave and quantum characteristics of light have to be considered for the function and applications of these devices.
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- Information
- Photonic Devices , pp. 3 - 70Publisher: Cambridge University PressPrint publication year: 2005