标题： 利用孤子微波梳实现高频谱效率的相干超通道传输 显示英文标题

标题： Enabling high spectral efficiency coherent superchannel transmission with soliton microcombs

摘要： 在过去三十年中，光通信系统在数据速率方面实现了五个数量级的提升。 数据流量需求的增加以及光电组件带宽的限制，导致最先进的系统在每个发射器中使用了数百个独立激光器。 鉴于光学放大器带宽有限，现在重点转向最大化频谱效率（SE）。 然而，相邻激光器的频率抖动会导致精确信道波长的不确定性，需要较大的保护频带来避免灾难性的信道重叠。 具有最佳线间距（通常约为10-50 GHz）的光频梳可以克服这些限制并最大化频谱效率。 基于微谐振器的孤子光频梳（以下简称微频梳）的最新发展，为光通信提供了一种紧凑、功耗低、多波长和相位锁定的光源。 在这里，我们展示了一个基于微频梳的通信链路，实现了此前仅在块状光学系统中才能实现的先进频谱效率。 与之前在光通信中的微频梳工作相比，我们的微频梳具有22.1 GHz的窄线间距。 此外，它提供的线间距稳定性比自由运行激光器高四个数量级。 光信噪比（OSNR）足以使用先进的高阶调制格式进行信息编码。 这使我们能够演示在82公里单段距离上传输12 Tb/s超通道，频谱效率超过10比特/秒/赫兹，以及在2000公里距离上传输，频谱效率高于6比特/秒/赫兹。 这些结果表明，微频梳可以达到将引领未来光网络的频谱效率。 显示英文摘要

摘要： Optical communication systems have come through five orders of magnitude improvement in data rate over the last three decades. The increased demand in data traffic and the limited optoelectronic component bandwidths have led to state-of-the-art systems employing hundreds of separate lasers in each transmitter. Given the limited optical amplifier bandwidths, focus is now shifting to maximize the spectral efficiency, SE. However, the frequency jitter from neighbouring lasers results in uncertainties of the exact channel wavelength, requiring large guardbands to avoid catastrophic channel overlap. Optical frequency combs with optimal line spacings (typically around 10-50 GHz) can overcome these limitations and maximize the SE. Recent developments in microresonator-based soliton frequency combs (hereafter microcombs) promise a compact, power efficient multi-wavelength and phase-locked light source for optical communications. Here we demonstrate a microcomb-based communication link achieving state-of-the-art spectral efficiency that has previously only been possible with bulk-optics systems. Compared to previous microcomb works in optical communications, our microcomb features a narrow line spacing of 22.1 GHz. In addition, it provides a four order-of-magnitude more stable line spacing compared to free-running lasers. The optical signal-to-noise ratio (OSNR) is sufficient for information encoding using state-of-the-art high-order modulation formats. This enables us to demonstrate transmission of a 12 Tb/s superchannel over distances ranging from a single 82 km span with an SE exceeding 10 bits/s/Hz, to 2000 km with an SE higher than 6 bits/s/Hz. These results demonstrate that microcombs can attain the SE that will spearhead future optical networks.