近日，美国斯坦福大学的Alexander D. White&Geun Ho Ahn及其研究团队取得一项新进展。经过不懈努力，他们实现硅芯片上的统一激光稳定与隔离。相关研究成果已于2024年10月15日在国际知名学术期刊《自然—光子学》上发表。

据悉，光子学的飞速发展催生了大量集成器件的涌现，这些器件有望在纳米尺度上实现与台式技术相同的性能，预示着下一代光学通信、传感与测量以及量子技术的到来。然而，高性能激光系统多组件共集成的挑战，使得这些纳米级器件的应用受到阻碍，因为所采用的激光源体积庞大，比器件本身要大出几个数量级。

该研究团队展示了高性能激光器的两大核心组件——降噪与隔离——可以同时源自一个单一、无源且与CMOS兼容的纳米光子器件，从而避免了不兼容技术的组合需求。为实现这一点，研究人员利用高品质因数氮化硅环形谐振腔的长光子寿命和非互易克尔非线性特性，对半导体激光芯片进行自注入锁定，同时提供隔离功能。

研究人员还发现了当前片上激光架构中此前未被认识到的功率范围限制，而该研究的系统能够克服这一限制。利用被称之为统一激光稳定器的器件，研究人员展示了一个具有内置隔离和降噪功能的片上集成激光系统，该系统以即用型可靠性运行。这种方法不同于直接微型化和集成传统激光系统组件的尝试，有助于弥合迈向全集成光学技术的差距。

附：英文原文

Title: Unified laser stabilization and isolation on a silicon chip

Author: White, Alexander D., Ahn, Geun Ho, Luhtaru, Richard, Guo, Joel, Morin, Theodore J., Saxena, Abhi, Chang, Lin, Majumdar, Arka, Van Gasse, Kasper, Bowers, John E., Vukovi, Jelena

Issue&Volume: 2024-10-15

Abstract: Rapid progress in photonics has led to an explosion of integrated devices that promise to deliver the same performance as table-top technology at the nanoscale, heralding the next generation of optical communications, sensing and metrology, and quantum technologies. However, the challenge of co-integrating the multiple components of high-performance laser systems has left application of these nanoscale devices thwarted by bulky laser sources that are orders of magnitude larger than the devices themselves. Here we show that the two main components for high-performance lasers—noise reduction and isolation—can be sourced simultaneously from a single, passive, CMOS-compatible nanophotonic device, eliminating the need to combine incompatible technologies. To realize this, we take advantage of both the long photon lifetime and the non-reciprocal Kerr nonlinearity of a high-quality-factor silicon nitride ring resonator to self-injection lock a semiconductor laser chip while also providing isolation. We also identify a previously unappreciated power regime limitation of current on-chip laser architectures, which our system overcomes. Using our device, which we term a unified laser stabilizer, we demonstrate an on-chip integrated laser system with built-in isolation and noise reduction that operates with turnkey reliability. This approach departs from efforts to directly miniaturize and integrate traditional laser system components and serves to bridge the gap to fully integrated optical technologies.

DOI: 10.1038/s41566-024-01539-3

Source: https://www.nature.com/articles/s41566-024-01539-3