Investigation of PPLN-Based PSAs for High-Gain Optical Amplification
Drummond, M. V.
; Puttnam, B. J.
; Wada, N.
Journal of Lightwave Technology Vol. 33, Nº 13, pp. 2802 - 2810, July, 2015.
ISSN (print): 0733-8724
Journal Impact Factor: 2,567 (in 2015)
Digital Object Identifier: 10.1109/JLT.2015.2413932
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In this paper, different configurations of phasesensitive
amplifiers (PSAs) built with periodically poled lithium
niobate (PPLN) devices are theoretically and numerically investigated,
focusing on their application for amplification in optical
communications systems. Single- and dual-pump configurations of
one-, two-, and four-mode PSAs are discussed. For each configuration,
analytical expressions for the maximum and minimum gain
of the amplifiers are provided, showing the influence of the power
of the pump and signal waves, as well as the length and efficiency of
the PPLN waveguide. The analytical expressions are numerically
validated by solving the coupled differential equations describing
the nonlinear interactions in the PPLN. The obtained results show
that the gain of all PSA configurations exponentially increases with
the power of the pump waves, and the length and efficiency of the
PPLN device, whereas it is almost independent of the power of the
signal wave. In addition, it is shown in this paper that PSA configurations
where an intermediate interaction is necessary to generate
waves at the second-harmonic band have a gain penalty of 6 dB. It
is also shown that no significant difference in terms of gain bandwidth
is observed for the single- and dual-pump configurations
of two-mode PSAs with an intermediate interaction. Finally, it is
shown that a four-mode PSA can only be implemented under very
strict conditions, with no gain advantage over two-mode PSAs.