Fiber-based optical parametric amplifiers and their applications

TLDR

Parametric amplifiers in fiber communications offer high gain, low noise, and versatile wavelength conversion, enabling applications such as all‑optical sampling, time‑demultiplexing, pulse generation, and WDM capacity enhancement, and recent advances suggest further progress with novel fibers and high‑power pumps. This review surveys applications of fiber‑based optical parametric amplifiers in communications. The review discusses the underlying four‑photon mixing theory and compares parametric amplifiers to Raman amplifiers, highlighting design considerations for fiber type and pump wavelength.

Abstract

An applications-oriented review of optical parametric amplifiers in fiber communications is presented. The emphasis is on parametric amplifiers in general and single pumped parametric amplifiers in particular. While a theoretical framework based on highly efficient four-photon mixing is provided, the focus is on the intriguing applications enabled by the parametric gain, such as all-optical signal sampling, time-demultiplexing, pulse generation, and wavelength conversion. As these amplifiers offer high gain and low noise at arbitrary wavelengths with proper fiber design and pump wavelength allocation, they are also candidate enablers to increase overall wavelength-division-multiplexing system capacities similar to the more well-known Raman amplifiers. Similarities and distinctions between Raman and parametric amplifiers are also addressed. Since the first fiber-based parametric amplifier experiments providing net continuous-wave gain in the for the optical fiber communication applications interesting 1.5-/spl mu/m region were only conducted about two years ago, there is reason to believe that substantial progress may be made in the future, perhaps involving "holey fibers" to further enhance the nonlinearity and thus the gain. This together with the emergence of practical and inexpensive high-power pump lasers may in many cases prove fiber-based parametric amplifiers to be a desired implementation in optical communication systems.