近日，美国哈佛大学Yang, Kiyoul团队研究了铌酸锂薄膜上的混合克尔-电光频率梳。相关论文于2025年8月12日发表在《光：科学与应用》杂志上。

光频梳是连接光和微波领域不可缺少的环节。芯片级集成保证了紧凑、可扩展和节能的频率梳强度，这是由共振增强的克尔效应或电光效应实现的。虽然利用前者的梳子可以达到八度频宽，而基于后者的梳子可以具有微波速率间隔，但同时实现这两种特性是具有挑战性的。

研究组同时利用薄膜铌酸锂的强克尔效应和电光效应，其中耗散克尔孤子产生之后是电光相位调制，实现了一个集成的频率梳参考，其中2589条线间隔为29.308GHz和75.9THz（588nm）。此外，研究组还演示了这种方法自然促进的梳间距的电子稳定和控制。该工作中的宽带微波速率频率梳克服了非线性集成频率梳源中存在的间距-跨度权衡，为下一代激光光谱学、微波和毫米波合成以及光通信的芯片级解决方案铺平了道路。

附：英文原文

Title: Hybrid Kerr-electro-optic frequency combs on thin-film lithium niobate

Author: Song, Yunxiang, Hu, Yaowen, Lonar, Marko, Yang, Kiyoul

Issue&Volume: 2025-08-12

Abstract: Optical frequency combs are indispensable links between the optical and microwave domains. Chip-scale integration promises compact, scalable, and power-efficient frequency comb sources, enabled by the resonantly-enhanced Kerr effect or the electro-optic effect. While combs utilizing the former can reach octave-spanning bandwidths, and combs based on the latter can feature microwave-rate spacings, achieving both features at the same time has been challenging. Here, we simultaneously leverage the strong Kerr and electro-optic effects on thin-film lithium niobate, where dissipative Kerr soliton generation is followed by electro-optic phase modulation, to realize an integrated frequency comb reference with 2,589 lines spaced by 29.308GHz and spanning 75.9THz (588nm). Further, we demonstrate electronic stabilization and control of the comb spacing, naturally facilitated by this approach. The broadband, microwave-rate frequency comb in our work overcomes the spacing-span tradeoff that exists in nonlinear integrated frequency comb sources, paving the way towards chip-scale solutions for next-generation laser spectroscopy, microwave and millimeter wave synthesis, as well as optical communications.

DOI: 10.1038/s41377-025-01906-x

Source: https://www.nature.com/articles/s41377-025-01906-x