Three-dimensional (3D) nano-printing of freeform optical waveguides, also referred to as photonic wire bonding, allows for efficient coupling between photonic chips and can greatly simplify optical system assembly. As a key advantage, the shape and the trajectory of photonic wire bonds can be adapted to the mode-field profiles and the positions of the chips, thereby offering an attractive alternative to conventional optical assembly techniques that rely on technically complex and costly high-precision alignment. However, while the fundamental advantages of the photonic wire bonding concept have been shown in proof-of-concept experiments, it has so far been unclear whether the technique can also be leveraged for practically relevant use cases with stringent reproducibility and reliability requirements. In this paper, we demonstrate optical communication engines that rely on photonic wire bonding for connecting arrays of silicon photonic modulators to InP lasers and single-mode fibres. In a first experiment, we show an eight-channel transmitter offering an aggregate line rate of 448 Gbit/s by low-complexity intensity modulation. A second experiment is dedicated to a four-channel coherent transmitter, operating at a net data rate of 732.7 Gbit/s - a record for coherent silicon photonic transmitters with co-packaged lasers. Using dedicated test chips, we further demonstrate automated mass production of photonic wire bonds with insertion losses of (0.7 ± 0.15) dB, and we show their resilience in environmental-stability tests and at high optical power. These results might form the basis for simplified assembly of advanced photonic multi-chip systems that combine the distinct advantages of different integration platforms.

中文翻译：

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通过原位3D纳米光刻技术对光通信引擎进行混合多芯片组装。

自由形式的光波导的三维（3D）纳米印刷，也称为光子引线键合，可实现光子芯片之间的有效耦合，并可大大简化光学系统的组装。作为一个关键优势，光子丝焊的形状和轨迹可以适应模场轮廓和芯片的位置，从而为依赖于技术复杂且价格昂贵的高精度的传统光学组装技术提供了一种有吸引力的替代方案对准。但是，尽管在概念验证实验中已经表明了光子引线键合概念的基本优点，但目前尚不清楚该技术是否也可以用于具有严格的可重复性和可靠性要求的实际相关用例。在本文中，我们演示了依靠光子引线键合将硅光子调制器阵列连接到InP激光器和单模光纤的光通信引擎。在第一个实验中，我们展示了一个八通道发射机，它通过低复杂度强度调制提供了448 Gbit / s的总线速。第二个实验专用于四通道相干发射机，其净数据速率为732.7 Gbit / s，这是带有共封装激光器的相干硅光子发射机的记录。使用专用的测试芯片，我们进一步演示了光电子丝键合的自动化批量生产，其插入损耗为（0.7±0.15）dB，并且在环境稳定性测试和高光功率下显示了它们的弹性。