Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden.
Nokia Bell Labs, 791 Holmdel Road, Holmdel, NJ, 07733, USA.
Nat Commun. 2018 Jun 28;9(1):2513. doi: 10.1038/s41467-018-04956-5.
The capacity and reach of long-haul fiber optical communication systems is limited by in-line amplifier noise and fiber nonlinearities. Phase-sensitive amplifiers add 6 dB less noise than conventional phase-insensitive amplifiers, such as erbium-doped fiber amplifiers, and they can provide nonlinearity mitigation after each span. Realizing a long-haul transmission link with in-line phase-sensitive amplifiers providing simultaneous low-noise amplification and nonlinearity mitigation is challenging and to date no such transmission link has been demonstrated. Here, we demonstrate a multi-channel-compatible and modulation-format-independent long-haul transmission link with in-line phase-sensitive amplifiers. Compared to a link amplified by conventional erbium-doped fiber amplifiers, we demonstrate a reach improvement of 5.6 times at optimal launch powers with the phase-sensitively amplified link operating at a total accumulated nonlinear phase shift of 6.2 rad. The phase-sensitively amplified link transmits two data-carrying waves, thus occupying twice the bandwidth and propagating twice the total power compared to the phase-insensitively amplified link.
长距离光纤通信系统的容量和覆盖范围受到在线放大器噪声和光纤非线性的限制。相敏放大器比传统的相敏放大器（如掺铒光纤放大器）添加的噪声少 6dB，并且可以在每个跨度后提供非线性缓解。实现具有在线相敏放大器的长距离传输链路，同时提供低噪声放大和非线性缓解是具有挑战性的，迄今为止，尚未展示出这样的传输链路。在这里，我们展示了一种具有在线相敏放大器的多通道兼容和调制格式独立的长距离传输链路。与由传统掺铒光纤放大器放大的链路相比，我们在最佳发射功率下演示了 5.6 倍的传输距离，而相敏放大链路的总累积非线性相移为 6.2rad。相敏放大链路传输两个携带数据的波，因此与相敏放大链路相比，它占用两倍的带宽并传播两倍的总功率。
