使用连续波泵浦的周期极化铌酸锂（PPLN）波导实现噪声系数低于3 dB量子极限的相敏放大。

Phase sensitive amplification with noise figure below the 3 dB quantum limit using CW pumped PPLN waveguide.

作者信息

Asobe Masaki, Umeki Takeshi, Tadanaga Osamu

机构信息

NTT Photonics Laboratories, NTT Corporation, 3-1, Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan.

出版信息

Opt Express. 2012 Jun 4;20(12):13164-72. doi: 10.1364/OE.20.013164.

DOI:10.1364/OE.20.013164

PMID:22714344

Abstract

The noise figure (NF) of a phase sensitive amplifier (PSA) based on a periodically poled LiNbO3 (PPLN) waveguide was evaluated in the optical and electrical domains. Phase sensitive amplification was realized using degenerate parametric amplification in the PPLN waveguide, which was pumped by the second harmonic frequency of the signal. Second harmonic pumping enables direct observation of the intrinsic amplified spontaneous emission (ASE), which determined the NF of the PSA. An NF below the 3 dB quantum limit was obtained by observing the intrinsic ASE. The low NF was also confirmed via the noise floor measurement of a cascaded PSA and erbium doped fiber amplifier in the electrical domain. The PSA was used as a preamplifier for detecting a 40 Gbit/s phase shift keying signal. The low noise characteristics were confirmed by the improved sensitivity.

摘要

对基于周期性极化铌酸锂（PPLN）波导的相敏放大器（PSA）的噪声系数（NF）在光学和电学领域进行了评估。在PPLN波导中利用简并参量放大实现相敏放大，该波导由信号的二次谐波频率泵浦。二次谐波泵浦使得能够直接观察到本征放大自发辐射（ASE），它决定了PSA的NF。通过观察本征ASE获得了低于3 dB量子极限的NF。在电学领域中，通过对级联PSA和掺铒光纤放大器的本底噪声测量也证实了低NF。该PSA用作检测40 Gbit/s相移键控信号的前置放大器。通过提高的灵敏度证实了其低噪声特性。