Abstract

When processing a data carrying signal with amplitude saturation in a fibre-optic parametric amplifier, the signal can be subject to a deleterious conversion of its amplitude noise into phase noise. To overcome this, we propose and demonstrate a scheme in which the products of four-wave mixing are instead synthesised using spectral shaping of multicast replicas of the signal, rather than naturally through four-wave mixing itself. This allows us to emulate the advancement of four-wave mixing without incurring unwanted amplitude noise to phase noise conversion. A final stage of four-wave mixing is used to bring about amplitude squeezing, with little impact on the phase noise of the signal. Using this technique, we are able to demonstrate phase preserving amplitude squeezing of a 10 GBd QPSK signal using as a medium, a highly nonlinear fibre in which the traditional, single pump approach fails.

Optimisation of amplitude limiters for phase preservation based on the exact solution to degenerate four-wave mixing

K. R. H. Bottrill, G. Hesketh, F. Parmigiani, D. J. Richardson, and P. Petropoulos
Opt. Express 24(3) 2774-2787 (2016)

Optical subcarrier processing for Nyquist SCM signals via coherent spectrum overlapping in four-wave mixing with coherent multi-tone pump

Guo-Wei Lu, Ruben S. Luís, José Manuel Delgado Mendinueta, Takahide Sakamoto, and Naokatsu Yamamoto
Opt. Express 26(2) 1488-1496 (2018)

Adaptive delay control for time-interleaved multi-channel amplitude limiter based on saturation of four-wave mixing in a fiber

Nor Shahida Mohd Shah, Masaru Sato, and Masayuki Matsumoto
Opt. Express 19(22) 21246-21257 (2011)

Signal phase regeneration through multiple wave coherent addition enabled by hybrid optical phase squeezer

Takayuki Kurosu, Hung Nguyen Tan, Karen Solis-Trapala, and Shu Namiki
Opt. Express 23(21) 27920-27930 (2015)

QPSK-to-2×BPSK wavelength and modulation format conversion through phase-sensitive four-wave mixing in a highly nonlinear optical fiber

Francesco Da Ros, Kjeld Dalgaard, Lei Lei, Jing Xu, and Christophe Peucheret
Opt. Express 21(23) 28743-28750 (2013)