Broadband highly efficient nonlinear optical processes in on-chip integrated lithium niobate microdisk resonators of Q-factor above 108
Broadband highly efficient nonlinear optical processes in on-chip integrated lithium niobate microdisk resonators of Q-factor above 108
复制标题
Q 因子高于 10(8) 的片上集成铌酸锂微盘谐振器中的宽带高效非线性光学过程
DOI：
10.1088/1367-2630/ac3d52
复制
发表时间：
2021-12-01
影响因子：
3.3
通讯作者：
Cheng, Ya
中科院分区：
文献类型：
--
作者：
Gao, Renhong;Zhang, Haisu;Cheng, Ya
微谐振器的质量（Q）的因素代表了一个关键类型的光子器件，旨在超高光谱分辨率，超高灵敏度的环境扰动，并在低阈值泵浦功率的有效的非线性波长转换。高Q值的绝缘体上叠层锂（LNOI）微盘由于其大的二阶非线性系数和强的电光特性而备受关注。在这封信中，我们突破了长期存在的瓶颈，在实现的LNOI微谐振器的Q值超过10（8），接近本征材料吸收限制的锂（LN）。超高的Q值引起了从光参量振荡（OPO）到谐波产生的丰富的非线性光学现象家族，具有前所未有的特性，包括超低的泵浦阈值、高的波长转换效率和超宽的操作带宽。具体而言，OPO的阈值被测量为只有19.6 μ W，在二次谐波产生中观察到的绝对转换效率达到23%。片上超高Q LNOI微谐振器的破纪录性能将对光子学研究和工业产生深远的影响。
Microresonators of ultrahigh quality (Q) factors represent a crucial type of photonic devices aiming at ultra-high spectral resolution, ultra-high sensitivity to the environmental perturbations, and efficient nonlinear wavelength conversions at low threshold pump powers. Lithium niobate on insulator (LNOI) microdisks of high Q factors are particularly attractive due to its large second-order nonlinear coefficient and strong electro-optic property. In this letter, we break through the long standing bottleneck in achieving the Q factors of LNOI microresonators beyond 10(8), which approaches the intrinsic material absorption limit of lithium niobate (LN). The ultra-high Q factors give rise to a rich family of nonlinear optical phenomena from optical parametric oscillation (OPO) to harmonics generation with unprecedented characteristics including ultra-low pump threshold, high wavelength conversion efficiency, and ultra-broad operation bandwidth. Specifically, the threshold of OPO is measured to be only 19.6 mu W, and the absolute conversion efficiency observed in the second harmonic generation reaches 23%. The record-breaking performances of the on-chip ultra-high Q LNOI microresonators will have profound implication for both photonic research and industry.