Fiber-based optical parametric amplifiers and their applications

Abstract

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 will also be 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-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.

Four-wave mixing UV generation in optical microfibers

“…Four wave mixing (FWM) is a parametric nonlinear process whereby two 'pump' photons are annihilated and converted into two 'new' photons, called the idler and signal, at different wavelengths via the Kerr nonlinearity of a medium [19]. There are two conditions for efficient FWM, namely, the energy conservation condition and the phase matching condition, which can be written as,…”

Full and semi-analytic analyses of two-pump parametric amplification with pump depletion

“…(1) is by assuming that the pump powers remain much greater than the signal and idler power at all times and that the power loss of the pumps is negligible [1]. This will quasi-linearize the differential equations and for pumps with identical power, P p , result in…”

“…Δβ is the wave-number mismatch given as Δβ = β 1 − β 2 − β 3 + β 4 , and since P p is the pump power in each pump and these are assumed identical, the expression resembles the expression known from single-pumped parametric amplifiers [1]. Generally, gain exists when −6γPp < Δβ < 2γPp, but the greatest gain, G(z) = P s (z)/P s (0), is obtained with κ = 0, thus requiring that Δβ = −2γP p .…”

“…There are several reasons for this, including their ability to provide phase-sensitive amplification [1][2][3], multicasting [4], regeneration [3,[5][6][7] and wavelength conversion [8,9]. It is noted that especially when applying the FOPA as an amplifier or regenerator, most emphasis has been on single-pumped amplifiers.…”

Simple geometric interpretation of signal evolution in phase-sensitive fibre optic parametric amplifier

“…Recently, fiber OPA has attracted a great deal of renewed interest as a promising technology for low-noise parametric amplification in high-capacity optical communications [3][4][5][6][7][8][9][10][11][12]. This recent revival of rather classical field is strongly supported by advances in the technology of highlynonlinear fibers (HNLF) with a good figure of merit (high nonlinear coefficient with a reasonably low losses).…”