Li Guangzhen, Chen Yuping, Jiang Haowei, Chen Xianfeng
Opt Lett. 2017 Mar 1;42(5):939-942. doi: 10.1364/OL.42.000939.
We demonstrate the first, to the best of our knowledge, type-0 broadband sum-frequency generation (SFG) based on single-crystal periodically poled LiNbO (PPLN) thin film. The broad bandwidth property was largely tuned from mid-infrared region to the telecommunications band by engineering the thickness of PPLN from bulk crystal to nanoscale. It provides SFG a solution with both broadband and high efficiency by using the highest nonlinear coefficient d instead of d in type-I broadband SFG or second-harmonic generation. The measured 3 dB upconversion bandwidth is about 15.5 nm for a 4 cm long single crystal at 1530 nm wavelength. It can find applications in chip-scale spectroscopy, quantum information processing, LiNbO-thin-film-based microresonator and optical nonreciprocity devices, etc.
据我们所知，我们首次展示了基于单晶周期性极化铌酸锂（PPLN）薄膜的0型宽带和频产生（SFG）。通过将PPLN的厚度从体晶体调整到纳米尺度，宽带特性在很大程度上从中红外区域调谐到了电信波段。它通过使用最高的非线性系数d而不是I型宽带SFG或二次谐波产生中的d，为SFG提供了一种兼具宽带和高效率的解决方案。对于波长为1530nm、长度为4cm的单晶，测得的3dB上转换带宽约为15.5nm。它可应用于芯片级光谱学、量子信息处理、基于铌酸锂薄膜的微谐振器和光学非互易器件等领域。
