title: 3-dB signal-ASE beat noise reduction of coherent multi-carrier signal utilizing phase sensitive amplification.
abstract: We demonstrated the simultaneous amplification of a coherent multi-carrier signal using a χ(2)-based non-degenerate phase sensitive amplifier (PSA). The signal-to-noise ratio (SNR), which is degraded by the additional amplified spontaneous emission (ASE) noise, can be recovered due to the gain difference between a phase-correlated signal-idler pair and uncorrelated excess noise. Utilizing the second harmonic pumping of a χ(2)-based PSA enables us to observe the SNR recovery directly by comparing the SNR for the input with that for the PSA output. A 3-dB optical-SNR (OSNR) improvement was obtained as a result of the gain difference. We also achieved a 3-dB SNR improvement in the electric domain by reducing the signal-ASE beat noise. The receiver sensitivity for a 10 Gbit/s phase shift keying signal was clearly improved with the PSA.
authors.affiliation: NTT Photonics Labs, NTT Corporation, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan. umeki.takeshi@lab.ntt.co.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Umeki
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Takara
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Masaki
authors.initials: M
authors.lastname: Asobe