laser diode

A semiconductor single-junction diode that (a) consists of positive and negative carrier regions with a positive-negative junction, i.e., a transition region, (b) emits electromagnetic energy, i.e., quanta of energy, at optical frequencies when injected electrons under forward bias recombine with holes in the vicinity of the junction, (c) is made of materials, such as gallium arsenide, that have a high probability of radiative recombination thus producing emitted light, rather than heat, at a frequency suitable for optical waveguides, such as optical fibers, optical integrated circuits (OICs), and slab dielectric waveguides, and (d) has polished ends that reflect and trap light to produce laser action, cause increased excitation, overcome losses, and produce increased emission. Common abbreviation LD. Note:Typical characteristics of a GaAlAs-type laser diode for fiber optic communications applications are (a) an 0.80-μm (micron) operating wavelength, (b) a 1-mW (milliwatt) to 40-mW...