An optical amplifier is a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal. An optical amplifier may be thought of as a laser without an optical cavity, or one in which feedback from the cavity is suppressed. Optical amplifiers are important in optical communication and laser physics.
There are several different physical mechanisms that can be used to amplify a light signal, which correspond to the major types of optical amplifiers. In doped fiber amplifiers and bulk lasers, stimulated emission in the amplifier's gain medium causes amplification of incoming light. In semiconductor optical amplfiers (SOAs), electron-hole recombination occurs. In Raman amplifiers, Raman scattering of incoming light with phonons in the lattice of the gain medium produces photons coherent with the incoming photons. Parametric amplifiers use parametric amplfication.
... An optical parametric amplifier allows the amplification of a weak Signal-Impulse in a noncentrosymmetric nonlinear medium (e.g ... In contrast to the previously mentioned amplifiers, which are mostly used in telecommunication environments, this type finds its main application in expanding the frequency tunability of ultrafast solid ... By using a noncollinear interaction geometry Optical Parametric Amplifiers are capable of extremely broad amplification bandwidths ...
Famous quotes containing the word optical:
“There is an optical illusion about every person we meet.”
—Ralph Waldo Emerson (18031882)