[发明专利]一种低损耗低串扰椭圆芯少模光纤

说明书

本发明提出了一种低损耗低串扰椭圆芯少模光纤；光纤由阶跃折射率分布的纯二氧化硅椭圆纤芯、折射率沟槽和包层组成；打破了空间模式简并、实现了保模功能，具有低本征损耗、低串扰的优点；采用凹陷的折射率包层有效减小了弯曲损耗。

技术领域

本发明涉及一种低损耗低串扰椭圆芯少模光纤，可应用于光纤光学、光纤通信、光纤无线接入、光学信息处理和新一代信息技术等领域。

背景技术

随着云计算、大数据、短视频等各种通信业务与日俱增的发展，单模光纤传输系统容量已无法满足更多的通信业务需求，模分复用作为解决单模光纤的通信容限或频谱效率问题的有效途径，受到广泛的关注，成为新一代光纤通信领域的研究热点[Miyamoto Y,Shibahara K,Mizuno T,and Kobayashi T.Mode-Division Multiplexing Systems forHigh-Capacity Optical Transport Network.In:Optical Fiber CommunicationConference.San Diego,California United States(2019)；Liang X,Li W,Wood WA,Downie JD,Hurley JE,and Ng’oma A.Transmission of wireless signals using spacedivision multiplexing in few mode fibers.Opt Express(2018)26:20507-20518；Sillard P,Bigot-Astruc M,and Molin D.Few-Mode Fibers for Mode-Division-Multiplexed Systems.J Lightwave Technol(2014)32:2824-2829；Richardson DJ,FiniJM,and Nelson LE.Space-division multiplexing in optical fibres.NaturePhotonics(2013)7(5):354-362；Li G,Bai N,Zhao N,and Xia C.Space-divisionmultiplexing:the next frontier in optical communication.Adv Opt Photon(2014)6(4):413-487；Li Y,Wang X,Zheng H,Li X,Bai C,Hu W,et al.A novel six-core few-mode fiber with low loss and low crosstalk.Optical Fiber Technology(2020)57:102-211.；Liu Y,Dong Q,Zheng H,Li X,Bai C,Hu W,et al.Research on a novel modedivision multiplexer with low crosstalk,low loss and few-mode ring-coretransmission channel.J Optics Communications(2020)469:125778-1-89；Bai N,Ip E,Luo Y,Peng G,Wang T,and Li G.Experimental Study on Multimode Fiber AmplifierUsing Modal Reconfigurable Pump.In:Optical Fiber Communication Conference.LosAngeles,California United States(2012)；Jung Y,Lim EL,Kang Q,May-Smith TC,WongNHL,Standish R,et al.Cladding pumped few-mode EDFA for mode divisionmultiplexed transmission.Opt Express(2014)22(23):29008-29013；郑宏军，黎昕，白成林，啁啾脉冲在光纤中的传输，北京：科学出版社，2018.1，1-184；董秋焕，刘阳，郑宏军，黎昕，白成林，胡卫生，陈南光.模分复用系统中少模复用(解复用)技术研究[J].聊城大学学报(自然科学版)，2020，33(2):50-67；王潇，郑宏军*(通讯作者)，黎昕，刘阳，于如愿，白成林，胡卫生，模分复用系统中的少模光纤研究新进展，聊城大学学报(自然科学版),2019.4，32(2):69-79；高艳，李严蕾，邢化东，黎昕，郑宏军*(通讯作者)，白成林，胡卫生，许恒迎，尹莹欣，董秋焕，模分复用光传输，聊城大学学报(自然科学)2022，35(1):30-56]；少模光纤作为模分复用系统中信息传输的载体一般采用典型的渐变折射率和阶跃折射率分布的圆芯少模光纤。基于这类少模光纤的模分复用传输系统不断地刷新着频谱效率的实验记录[Rademacher G,Luís RS,Puttnam BJ,Ryf R,Furukawa H,Maruyama R,et al.93.34Tbit/s/mode(280Tbit/s)Transmission in a 3-Mode Graded-Index Few-Mode Fiber.In:Optical Fiber Communication Conference.San Diego,California United States(2018)；Soma D,Beppu S,Wakayama Y,Igarashi K,Tsuritani T,Morita I,et al.257-Tbit/s Weakly Coupled 10-Mode C+L-Band WDM Transmission.J Lightwave Technol(2018)36(6):1375-1381；Weerdenburg JV,Ryf R,Alvarado-Zacarias JC,Alvarez-Aguirre RA,Fontaine NK,Chen H,et al.138-Tb/s Mode-and Wavelength-MultiplexedTransmission Over Six-Mode Graded-Index Fiber.J Lightwave Technol(2018)36:1369-1374；Wakayama Y,Soma D,Beppu S,Sumita S,Igarashi K,and TsuritaniT.266.1-Tbit/s Transmission Over 90.4-km 6-Mode Fiber with Inline Dual C+L-Band6-Mode EDFA.J Lightwave Technol(2019)37:404-410；Beppu S,Soma D,Sumita S,Wakayama Y,Takahashi H,Tsuritani T,et al.402.7-Tb/s MDM-WDM Transmission OverWeakly Coupled 10-Mode Fiber Using Rate-Adaptive PS-16QAM Signals.J LightwaveTechnol(2020)38:2835-2841；Rademacher G,Puttnam BJ,Luís RS,Sakaguchi J,KlausW,Eriksson TA,et al.10.66Peta-Bit/s Transmission over a 38-Core-Three-ModeFiber.In:Optical Fiber Communication Conference.San Diego,California UnitedStates(2020)]；随着少模光纤的发展，传输的频谱效率不断提高。然而，模分复用系统采用的这类圆芯少模光纤存在着模式简并、模式间串扰问题。为了解决这些问题，需要使用MIMO-DSP方法处理，但模式数目越多会导致数据计算量、复杂度快速增加，从而导致短距离数据通信系统大延迟、巨大功耗和高成本等严重问题[Hu T,Li J,Ge D,Wu Z,Tian Y,ShenL,et al.Weakly-coupled4-mode step-index FMF and demonstration of IM/DD MDMtransmission.Opt Express(2018)26:8356-8363；Wang L,Nejad RM,Corsi A,Lin J,Messaddeq Y,Rusch LA,et al.MIMO-Free Transmission over Six Vector Modes in aPolarization Maintaining Elliptical Ring Core Fiber.In:Optical FiberCommunication Conference.Los Angeles,California United States(2017)；Hong K,Yeom J,Jang C,Hong J,and Lee B.Full-color lens-array holographic opticalelement for three-dimensional optical see-through augmented reality.Opt Lett(2014)39:127-130]。