摘要
基于微环谐振腔的微波光子滤波器(MPF)以其优异的可调谐特性得到了广泛关注和研究,但通常微环的带宽决定了所实现的MPF带宽,进而限制了滤波分辨率。本文提出并验证了一种基于三微环级联的MPF,相比单个微环,通过多引入两个微环谐振腔,使光载波与±1阶光边带拍频后的相位差谱从0~π变得更陡峭,从而实现了MPF带宽压缩。实验结果表明,本文提出的基于级联三微环的MPF在不提升微环本身Q值的前提下,相比基于单微环的MPF,滤波带宽压缩了约69%,3 dB衰减斜率提高了约3.6倍,实现了更精细的滤波;另外,该MPF还实现了11.5~20.3 GHz的频率连续调谐和187.1~1597.0 MHz的带宽连续调谐。
Objective Microwave photonic technology can process radio frequency(RF)signals in the optical domain.Compared with the traditional electrical processing methods,it has the advantages of low loss,broadband,good tunability,and sound anti-electromagnetic interference.As an important component for various applications such as radar,communications,and radio astronomy,microwave photonic filter(MPF)has become a research hotspot in microwave photonics in recent years.With the development of photonic integration technology,integrated MPFs have attracted research attention.Recently,microring resonators(MRRs)have been widely employed in MPFs thanks to their compact sizes and good adjustability.The MPF should have a narrow RF bandwidth to achieve precise RF resolution.As known,typically the RF bandwidth of the MPF based on MRR is the same as the optical bandwidth of the MRR when crosstalk is ignored.Therefore,reducing the optical bandwidth of the MRR by improving its quality factor(Q factor)is the most direct and effective way to reduce the MPF bandwidth.However,the MRR loss should be reduced to increase the Q factor,which is difficult to achieve since the scattering loss caused by the waveguide sidewall roughness is usually unavoidable.Under typical silicon-on-insulator(SOI)fabrication processes,optical bandwidth of about GHz for MRR can be obtained,which cannot meet the requirements of high-precision MPF with sub-GHz frequency resolving capability.We propose and demonstrate an MPF based on three cascaded MRRs and phase modulation.With this configuration,the 3-dB RF bandwidth of the MPF can be well compressed compared with the 3-dB optical bandwidth of the MRR,and flexible tunability of the MPF is achieved.Methods We put forward an MPF based on cascaded three MRRs and phase modulation.By introducing two more MRRs,the phase differences between the optical carrier and the±1 order optical sidebands can be changed much steeper from 0-πcompared with the MPF constructed by a single MRR.As a result,the photocurrent obtained by b
作者
王鹏飞
程威
苍昭
田庄
梁梓恩
郭宸
刘宇航
恽斌峰
Wang Pengfei;Cheng Wei;Cang Zhao;Tian Zhuang;Liang Zien;Guo Chen;Liu Yuhang;Yun Binfeng(Advanced Photonics Center,Southeast University,Nanjing 210096,Jiangsu,China;School of Electronic Science&Engineering,Southeast University,Nanjing 210096,Jiangsu,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2023年第22期188-196,共9页
Acta Optica Sinica
基金
国家自然科学基金(62171118)。
关键词
集成光学
微环谐振腔
微波光子滤波器
带宽
可调谐性
integrated optics
microring resonators
microwave photonic filter
bandwidth
tunability
