[发明专利]一种低损耗低串扰两模式超模光纤

说明书

本发明提出了一种低损耗低串扰两模式超模光纤；光纤由三个具有渐变折射率分布的纯二氧化硅纤芯、折射率沟槽和掺氟二氧化硅包层组成；实现了高模场密度、低损耗、低色散、低串扰的超模运作，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两模式超模光纤，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

近年来，随着各种通信业务流量指数增长，单模光纤通信受到了前所未有的挑战。光纤通信业界围绕空分复用(包括芯式复用和模分复用及其结合)这一物理维度对通信网络传输容量实现了突破；空分复用中的多芯光纤、少模光纤、多芯少模光纤的研究成为前沿研究热点[Yutaka Miyamoto,Kohki Shibahara,Takayuki Mizuno,and TakayukiKobayashi.Mode-division multiplexing systems for high-capacity opticaltransport tetwork[C].Optical Fiber Communication Conference,2019,paper M2I.3；Jiaxiong Li,Chengkun Cai,Jiangbing Du,et al.Ultra-low-noise mode-divisionmultiplexed WDM transmission over 100-km FMF based on a second-order Few-moderaman amplifier[J].Journal of Lightwave Technology,2018,36(16):3254-3260；Ruyuan Yu,Hongjun Zheng,Xin Li,et al.A novel three-ring-core few-mode fiberwith large effective area and low nonlinear coefficient[J].OptoelectronicsLetters,2018,14(1):30-35；Seongjin Hong, Kyoungyeon Choi,Yong Soo Lee,andKyunghwan Oh.Two-mode fiber with a reduced mode overlap for uncoupled mode-division multiplexing in C+L band[J].Current Optics and Photonics,2018,2(3):233-240；Georg Rademacher,Roland Ryf,Nicolas K.Fontaine,et al. Long-haultransmission over Few-mode fibers with space-division multiplexing[J].Journalof Lightwave Technology，2018，36(6)：1382-1388；Tetsuya Hayashi,TakujiNagashima,Kazuhiro Yonezawa,et al.Six-mode 19-core fiber with 114spatialmodes for weakly-coupled mode-division-multiplexed transmission[J].Journal ofLightwave Technology，2017，35(4)： 748-754；He Wen,Hongjun Zheng,Qi Mo,etal.Few-mode fiber-optic microwave photonic links [J].Light:ScienceApplications,2017.8,6,e17021,1-8；Li Y,Wang X,Zheng H,Li X,Bai C,Hu W,et al.Anovel six-core few-mode fiber with low loss and low crosstalk.Optical FiberTechnology (2020)57:102211-.；Gao Yan,Li Yanlei,Li Xin,Zheng Hongjun,BaiChenglin,Hu Weisheng,Xu Hengying,Dong Qiuhuan,Xing Huadong,Su Yingqun,YinYingxin,Wei Chongqi,Zhao Baiqiang. An Elliptical-Core Few-Mode Fiber with LowLoss and Low Crosstalk for the MIMO-FREE Applications.Frontiers in Physics(2022)9；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，2018，1-184；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,白成林,胡卫生,许恒迎,尹莹欣,董秋焕.模分复用光传输技术研究[J].聊城大学学报(自然科学版),2022,35(01):30-56]；多实芯强耦合的三芯超模光纤也得到了大家的关注；多实芯超模光纤本质上是具有更大的有效模场面积、模场密度大、低模式依赖损耗、低模式耦合等少模光纤[G.Rademacher,R.S.Luís,B.J.Puttnam,R.Ryf,S.van der Heide,T.A. Eriksson,N.K.Fontaine,H.Chen,R.Essiambre,Y.Awaji,H.Furukawa,and N.Wada,172Tb/s C+LBand Transmission over 2040km Strongly Coupled 3-Core Fiber,in Optical FiberCommunication Conference Postdeadline Papers 2020,(Optical Society ofAmerica,2020),paper Th4C.5；R.Ryf,R.-.Essiambre,A.H.Gnauck,S.Randel,M.A.Mestre,C.Schmidt,P.J.Winzer, R.Delbue,P.Pupalaikis,A.Sureka,T.Hayashi,T.Taru,and T.Sasaki,Space-Division Multiplexed Transmission over 4200-km 3-Core Microstructured Fiber,in Optical Fiber Communication Conference,OSATechnical Digest(Optical Society of America,2012),paper PDP5C.2；S.van derHeide,J.C.Alvarado-Zacarias,N.K.Fontaine,R.Ryf,H.Chen,R. Amezcua-Correa,T.Koonen,and C.Okonkwo,Low-loss Low-MDL Core Multiplexer for 3-Core Coupled-core Multi-core Fiber,in Optical Fiber Communication Conference(OFC)2020,OSATechnical Digest(Optical Society of America,2020),paper T3A.3；Ryf,RolandSierra,Alberto Essiambre,R.-JGnauck,A.H.Randel,SebastianEsmaeelpour,MinaMumtaz,Sami Winzer,PeterDelbue,R.Pupalaikis,PeterSureka,AnirudhHayashi,TetsuyaTaru, ToshikiSasaki,Takashi.(2011).Coherent 1200-km 6x 6MIMO Mode-Multiplexed Transmission over 3-Core Microstructured Fiber.1–3；R.Veronese,J.C.A.Zacarias,S.van der Heide,R.Amezcua-Correa,H.Chen,R.Ryf,N.K.Fontaine,M.Santagiustina,A.Galtarossa,and L.Palmieri,Distributed Supermode CouplingMeasurements in Multi-Core Optical Fibers, in Optical Fiber CommunicationConference(OFC)2020,OSA Technical Digest(Optical Society of America,2020),paper T4J.2]；纯二氧化硅纤芯可以有效地减少光纤衰减和熔接损耗，受到广泛关注，目前大都应用于单模光纤(T.Hasegawa et al.2016.Advances in ultra-low loss silicafibers[J].Frontiers in Optics,paper FTu2B.2；S.Ten.2016.Ultra Low-loss OpticalFiber Technology[J].Optical Fiber Communication Conference,paper Th4E.5；Yoshiaki Tamura.2018. Ultra-low loss silica core fiber for long haultransmission[J].Optical Fiber Communication Conference,paper M4B.1)。具有渐变折射率分布的少模光纤可以实现低差分模式群时延 DMGD以及远场和近场具有相同模式宽度，并且不同模式下的有效折射率差(ERID)大于 0.5x10^-3可以避免模式耦合(P.Sillardand D.Molin,A review of few-mode fibers for space-division multiplexedtransmissions,39th European Conference and Exhibition on OpticalCommunication(ECOC 2013),2013,1-3；Roland Ryf.Switching and MultiplexingTechnologies for Mode-Division Multiplexed Networks,Optical FiberCommunication ConferenceExposition, 2017,Tu2c)。综上，若将纯二氧化硅纤芯、渐变折射率分布及多实芯强耦合的超模光纤的概念有机融合，有望解决目前少模光纤的研究挑战，有重要的学术价值和应用价值，研究意义重大、应用前景广阔。