Tunable light sources are a key enabling technology for many applications such as ranging, spectroscopy, optical coherence tomography, digital imaging and interferometry. For miniaturized laser devices, whispering gallery resonator lasers are a well-suited platform, offering low thresholds and small linewidths, however, many realizations suffer from the lack of reliable tuning. Rare-earth ion-doped lithium niobate offers a way to solve this issue. Here we present a single-frequency laser based on a neodymium-doped lithium niobate whispering gallery mode resonator that is tuned via the linear electro-optic effect. Using a special geometry, we suppress higher-order transverse modes and hence ensure single-mode operation. With an applied voltage of just $68\,$V, we achieve a tuning range of $3.5\,$GHz. The lasing frequency can also be modulated with a triangular control signal. The freely running system provides a frequency and power stability of better than $Δν=20\,$MHz and 6%, respectively, for a 30 minute period. This concept is suitable for full integration with existing photonic platforms based on lithium niobate.
Monolithic integration of a high-quality factor lithium niobate microresonator with a free-standing membrane waveguide using femtosecond laser assisted ion beam writing (FLAIBW)
State Key Laboratory of Ultra-intense Laser Science and Technology, 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超快激光科学与技术国家重点实验室）；Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences（中国科学院大学材料科学与光电技术研究中心）；State Key Laboratory of Precision Spectroscopy, East China Normal University（华东师范大学精密光谱科学与技术国家重点实验室）；The Extreme Optoelectromechanics Laboratory (XXL), School of Physics and Electronic Science, East China Normal University（华东师范大学物理与电子科学学院极端光机电实验室）；Shanghai Research Center for Quantum Sciences（上海市量子科学研究中心）；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）
Experimental observation of internally-pumped parametric oscillation and quadratic comb generation in a $χ^{(2)}$ whispering-gallery-mode microresonator
Simultaneous generation of four-wave mixing and stimulated Raman scattering in coupled lithium niobate microdisks mediated by second harmonic generation
Polygon Coherent Modes in aWeakly Perturbed Whispering Gallery Microresonator for Efficient Second Harmonic, Optomechanic and Frequency Comb Generations
Quantum squeezing in an all-resonant periodically poled lithium niobate microresonator
University of California, Berkeley（加州大学伯克利分校）；Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California（南加州大学明海电气与计算机工程学院）；Materials Sciences Division, Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室材料科学部）
Multiple soliton regimes enabled by parametric down-conversion in $χ^{(2)}+χ^{(3)}$ microresonators
University of Bath（巴斯大学）；Centre for Photonics, University of Bath（巴斯大学光子学中心）；VTT Technical Research Centre of Finland（芬兰技术研究中心）；National Physical Laboratory（英国国家物理实验室）
Ultra-high-speed high-resolution laser lithography for lithium niobate integrated photonics
光刻辅助化学机械蚀刻（PLACE）是一种专门开发用于在薄膜锂酸盐（TFLN）上制造高质量大规模光子集成电路（PIC）的技术，其使得能够制造从高质量（高Q）微谐振器和低损耗波导到电光（EO）可调谐激光器和波导放大器的一系列PIC构建块。针对PIC器件和系统的高产量制造，我们已经开发了一种超高速高分辨率激光光刻制造系统，采用高重复频率飞秒激光和高速多边形激光扫描仪，通过该光刻制造系统，在200 nm的空间分辨率下，光刻制造效率为4.8 cm 2/h。我们展示了基于TFLN的光子结构，光学相位掩模以及彩色印刷的晶圆级制造
High-Q Lithium Niobate Microring Resonator with Electro-Optically Reconfigurable Coupling Strength
Shanghai Research Center for Quantum Sciences（上海量子科学研究中心）；State Key Laboratory of Precision Spectroscopy, East China Normal University（精密光谱学国家重点实验室，华东师范大学）；The Extreme Optoelectromechanics Laboratory (XXL), School of Physics, East China Normal University（极端光机电实验室（XXL），物理学院，华东师范大学）；WLSA Shanghai Academy（WLSA上海学院）；Hefei National Laboratory（合肥国家实验室）；Collaborative Innovation Center of Extreme Optics, Shanxi University（极端光学协同创新中心，山西大学）
Highly efficient multi-chromatic Raman microlasers from cavity polygon modes on thin-film lithium niobate platform
State Key Laboratory of Ultra-intense laser Science and Technology, 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）；The Extreme Optoelectromechanics Laboratory (XXL), School of Physics and Electronic Science, East China Normal University（华东师范大学物理与电子科学学院）；State Key Laboratory of Precision Spectroscopy, East China Normal University（华东师范大学）；Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences（中国科学院大学材料科学与光电工程学院）；Nanophotonics Research Center, Institute of Microscale Optoelectronics & State Key Laboratory of Radio Frequency Heterogeneous Integration, Shenzhen University（深圳大学微纳光子学研究中心）；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）
Offset Dual Microcombs in a Single Microresonator: Kerr-Raman Interleaved Combs
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）
