Analytical and Device-Related Applications of Nonlinear Optics

Nonlinear optics is a broad field of research and technology that encompasses subject matter in the fields of physics, chemistry, biology, and engineering. The diversity of nonlinear optics stems, in part, from the need for all-optical and electrooptical devices for applications in telecommunications, optical storage, and all-optical computing. In addition, many nonlinear optical effects have proved to be versatile probes of fundamental issues such as interfacial adsorption, the electronic structure of compound semiconductors, and phase transitions in liquid crystal films. This article discusses analytical and device applications that are based on second-order nonlinear interactions of light with matter. Particular attention is given to the exciting technique of infrared–visible sum-frequency generation, which illustrates the capability of the second-order nonlinear response in probing surface and interfacial phenomena. The connection between nonlinear optics and optical waveguides is discussed to demonstrate the potential of thin semiconductor films for efficient second-harmonic generation in the ultraviolet region of the spectrum.