Investigation of the noise figure in degenerate dual-pump phase sensitive amplifier using a multi-wave model

A semi-classical 7-wave model is developed to investigate the noise performances of a degenerate dual-pump phase sensitive amplifier. This approach takes into account the transfer to the signal, through multiple four-wave mixing processes, of the vacuum fluctuations injected in the high-order waves. This effect leads to a degradation of the noise figure of the amplifier with respect to the 0 dB value predicted by the usual 3-wave model. However, it is proved that a careful choice of the fiber dispersion allows to use the high-order waves to enhance the signal gain without degrading the noise figure above 1 dB.