There are three main types of optical amplifiers: EDFA, SOA, and FRA. Each type has its own good and bad points. It also means you do not need to. This article explains the fundamental principles of optical amplifiers, distinguishing between laser amplifiers, which use stimulated emission in a pumped gain medium (like fiber amplifiers and semiconductor optical amplifiers), and nonlinear amplifiers, which rely on effects like parametric. Optical amplifiers are used to create laser guide stars which provide feedback to the adaptive optics control systems which dynamically adjust the shape of the mirrors in the largest astronomical telescopes. SOA's work in a broader range, from 400-2000nm.
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