单片薄膜铌酸锂微环中产生的双光频梳
Dual-comb generated in single thin-film lithium niobate microrings
- East China Normal University（华东师范大学）
- Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences（中国科学院上海光学精密机械研究所）
- Nanjing University（南京大学）
- Shanghai Research Center for Quantum Sciences（上海量子科学研究与创新中心）
- Hefei National Laboratory（合肥国家实验室）
- Collaborative Innovation Center of Extreme Optics, Shanxi University（山西大学极端光学协同创新中心）
- Collaborative Innovation Center of Light Manipulations and Applications, Shandong Normal University（山东师范大学光调控与应用协同创新中心）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文首次在单个薄膜铌酸锂微环中，利用受激拉曼散射桥接两个模式族，在单一连续波激光泵浦下产生双光频梳，实现了低相位噪声和宽光谱覆盖，为片上集成双光频梳提供了稳健路径。
AI中文摘要：
双光频梳技术已成为高精度光谱学、实时测距和高灵敏度传感的重要工具。将双光频梳源集成到单个微谐振器中，将大幅降低泵浦功率、器件尺寸、系统复杂性和成本，但这仍然是一个重大挑战。在此，我们首次在单个薄膜铌酸锂（TFLN）微环中，在单一连续波激光泵浦下，演示了集成双光频梳的产生。与传统观点将TFLN的强拉曼非线性视为不利因素不同，我们将其建设性地加以利用。通过工程化设计TFLN微环的色散，我们利用了基阶和一阶横电模族，其加载品质因数超过5×10^6，重复率相当，且具有合适的色散分布，并通过受激拉曼散射（SRS）过程将它们桥接起来。在1551.28 nm处泵浦一阶模，首先在低阈值下于基模族中激发斯托克斯和反斯托克斯SRS，随后在320 mW的泵浦功率下，分别通过直接Kerr效应和拉曼辅助Kerr效应产生两个独立、光谱分离的光频梳。这两个光频梳覆盖宽带宽，重复率约为102 GHz，差异约为624 MHz，且光谱上不合并。最宽的光谱跨度达654 nm，拉曼-Kerr光频梳的3-dB带宽超过29 nm。进一步表征确认，光频梳线具有低相位噪声，固有线宽为410 Hz。这项工作为在单激光泵浦微环中实现片上双光频梳产生建立了一条稳健的路径，显著推动双光频梳系统向简化架构、增强稳健性和可扩展集成方向发展，同时加速其实际部署。
英文摘要：
Dual-comb technology has emerged as an essential tool for high-precision spectroscopy, real-time ranging, and high-sensitivity sensing. Integrating dual-comb sources into a single microresonator would substantially reduce pump power, footprint, system complexity, and cost, yet this remains a significant challenge. Here, we demonstrate, for the first time, integrated dual-comb generation in a single thin-film lithium niobate (TFLN) microring, under single continuous-wave laser pumping. Rather than regarding TFLN's strong Raman nonlinearity as detrimental, as conventionally viewed, we harness it constructively. By engineering the dispersion of TFLN microrings, we leverage the fundamental and first-order transverse-electric mode families with loaded Q factors exceeding 5X10^6, comparable repetition rates, and suitable dispersion profiles, and bridge them through stimulated Raman scattering (SRS) processes. Pumping a first-order mode at 1551.28 nm initially excites both Stokes and anti-Stokes SRS in the fundamental mode family at low thresholds, and subsequently produces two independent, spectrally separated combs at a pump power of 320 mW via direct Kerr and Raman-assisted Kerr effects, respectively. The two combs span broad bandwidths, exhibit repetition rates of ~102 GHz with a slight difference of ~624 MHz, and do not merge spectrally. The broadest spectrum spans 654 nm, and the Raman-Kerr comb has a 3-dB bandwidth exceeding 29 nm. Further characterization confirms that the comb lines exhibit low phase noise, with an intrinsic linewidth of 410 Hz. This work establishes a robust pathway for on-chip dual-comb generation in a single-laser pumped microring, significantly advancing dual-comb systems toward simplified architectures, enhanced robustness, and scalable integration, while accelerating their practical deployment.
