ABSTRACT
The interaction of optical signals with electrical elements has been an important part of the fields of solid-state and microwave electronics for many years. This association, especially through the areas of fiber-optic communications and optical computing, is ultimately leading to the situation whereby integrated optical and electronic systems are becoming just as important as either one of them on its own (Knox, 2000). Visible and infrared (especially the latter) photoconductors, photodiodes, phototransistors, laser diodes, electro-optic modulators, and a variety of other components are commonly used in optoelectronic telecommunications systems to convert optical signals to electric signals and to manipulate optical radiation. Furthermore, light can be used to control microwaves through the use of p-i-n and IMPATT diodes as well as other two-and three-terminal devices (e.g., see Mourou et al., 1985). Extending beyond traditional microwaves, optics is also found to be useful in the generation of submillimeter-wave radio frequencies (RF), commonly referred to as the terahertz (THz) regime (see, e.g., Coleman, 2000, and references therein). The utility of the opticalelectronic interactions in nearly all of these instances is further enhanced-or in some cases allowed only by-the employment of ultrashort-duration laser pulses from ultrafast lasers, compared to continuous-wave laser light or incoherent light. In these applications the short pulses are used as extremely fast trigger signals or for packing as much information into as small a time period as possible in ultrahigh bit rate communications systems.
