Reduction of quantum fluctuation and suppression of the Gordon–Haus effect with phase-sensitive linear amplifiers

Compared with the use of phase-insensitive linear quantum amplifiers of the same gain G, the use of phase-sensitive linear amplifiers on phase coherent classical light sources in an amplifier–attenuator chain reduces the total quantum noise power by a factor of 4, the homodyne noise variance by 2, and the photon number variance by 2–8 and suppresses the Kerr effect linear phase fluctuation variance as well as the soliton timing-error variance by 2G².