[1] Richardson D J, Fini J M, Nelson L E. Space-division multiplexing in optical fiber［J］. Nature Photonics, 2013, 7(5): 354-362.

[2] Essiambre R J, Kramer G, Winzer P J, et al. Capacity limits of optical fiber networks［J］. Journal of Lightwave Technology, 2010, 28(4): 662-701.

[3] Sakaguchi J, Puttnam B J, Klaus W, et al. 19-core fiber transmission of 19×100×172-Gb/s SDM-WDM-PDM-QPSK signals at 305 Tb/s［C］. Optical Fiber Communication Conference, 2012: PDP5C.1.

[4] Takara H, Sano A, Kobayashi T, et al. 1.01-Pb/s (12 SDM/222 WDM/456 Gb/s) crosstalk-managed transmission with 91.4-b/s/Hz aggregate spectral efficiency［C］. European Conference and Exhibition on Optical Communication, 2012: Th.3.C.1.

[5] Tu J, Saitoh K, Koshiba M, et al. Design and analysis of large-effective-area heterogeneous trench-assisted multi-core fiber［J］. Optics Express, 2012, 20(14): 15157-15170.

[6] Sakamoto T, Mori T, Yamamoto T, et al. Differential mode delay managed transmission line for WDM-MIMO system using multi-step index fiber［J］. Journal of Lightwave Technology, 2012, 30(17): 2783-2787.

[7] Sato K, Maruyama R, Kuwaki N, et al. Optimized graded index two-mode optical fiber with low DMD, large A(eff) and low bending loss［J］. Optics Express, 2013, 21(14): 16231-16238.

[8] Han J, Zhang J, Zhao Y, et al. Numerical demonstration of mode-division multiplexing transmission over dual-mode photonic crystal fiber enabled by fiber couplers［J］. Optik-International Journal for Light and Electron Optics, 2013, 124: 1287-1289.

[9] Munir A, Xin X, Liu B, et al. Numerical analysis of intermodal delay in few-mode fibers for mode division multiplexing in optical fiber communication systems［J］. Optoelectronics Letters, 2012, 8(2): 138-141.

[10] Sillard P, Bigot-Astruc M, Molin D. Few-mode fibers for mode-division-multiplexed systems［J］. Journal of Lightwave Technology, 2014, 32(16): 2824-2829.

[11] 刘业辉, 李进延. 多芯光纤激光器选模特性及其研究进展［J］. 激光与光电子学进展, 2016, 53(5): 050005.

    Liu Yehui, Li Jinyan. Mode properties and progress of multi-core fiber lasers［J］. Laser & Optoelectronics Progress, 2016, 53(5): 050005.

[12] 杨 芳, 唐 明, 李博睿, 等. 低串扰大模场面积多芯光纤的设计与优化［J］. 光学学报, 2014, 34(1): 0106005.

    Yang Fang, Tang Ming, Li Borui, et al. Design and optimization of multi-core fibers with low crosstalk and large effective area［J］. Acta Optica Sinica, 2014, 34(1): 0106005.

[13] 骆淑君, 王晓亮, 陈达如, 等. 多芯光纤及其在弯曲传感中的应用［J］. 光子学报, 2016, 45(2): 0206005.

    Luo Shujun, Wang Xiaoliang, Chen Daru, et al. Multi-core fiber and its application for bending sensor［J］. Acta Photonica Sinica, 2016, 45(2): 0206005.

[14] Takenaga K, Sasaki Y, Guan N, et al. Large effective-area few-mode multicore fiber［J］. IEEE Photonics Technology Letters, 2012, 24(21): 1941-1944.

[15] Xia C, Amezcuacorrea R, Bai N, et al. Low-crosstalk few-mode multi-core fiber for high-mode-density space-division multiplexing［C］. 38th European Conference and Exhibition on Optical Communications, 2012: Mo.1.F.5.

[16] Mizuno T, Kobayashi T, Takara H, et al. 12-coreⅹ3-mode dense space division multiplexed transmission over 40 km employing multi-carrier signals with parallel MIMO equalization［C］. Optical Fiber Communications Conference and Exhibition, 2014: Th5B.2.

[17] Tu J, Saitoh K, Takenaga K, et al. Heterogeneous trench-assisted few-mode multi-core fiber with low differential mode delay［J］. Optics Express, 2014, 22(4): 4329-4341.

[18] Sasaki Y, Amma Y, Takenaga K, et al. Few-mode multicore fiber with 36 spatial modes (three modes (LP01, LP11a, LP11b)×12 cores)［J］. Journal of Lightwave Technology, 2015, 33(5): 964-970.

[19] Tu J, Saitoh K, Amma Y, et al. Heterogeneous trench-assisted few-mode multi-core fiber with graded-index profile and square-lattice layout for low differential mode delay［J］. Optics Express, 2015, 23(12): 17783-17792.

[20] Tu J, Long K, Saitoh K. Design and optimization of 3-mode×12-core dual-ring structured few-mode multi-core fiber［J］. Optics Communications, 2016, 381: 30-36.

[21] Hanzawa N, Saitoh K, Sakamoto T, et al. Three-mode PLC-type multi/demultiplexer for mode-division multiplexing transmission［C］. European Conference and Exhibition on Optical Communication, 2013: Tu.1.B.3.

[22] Chen H, Uden R V, Okonkwo C, et al. Employing an integrated mode multiplexer on silicon-on-insulator for few-mode fiber transmission［C］. European Conference and Exhibition on Optical Communication, 2013: Tu.1.B.4.

[23] Fontine N K, Leon-saval S G, Ryf R, et al. Mode-selective dissimilar fiber photonic-lantern spatial multiplexers for few-mode fiber［C］. European Conference and Exhibition on Optical Communication, 2013: PD1.C.3.

[24] Zhou Q, Simmhan Y, Prasanna V. Tapered mode multiplexers based on standard single-mode fibre［C］. European Conference and Exhibition on Optical Communication, 2013: PD1.C.1.

[25] Uemura H, Sasaki Y, Nishimoto S, et al. Mode multiplexer/demultiplexer based on a partially elongated multi-core fiber［C］. Optical Fiber Communication Conference, 2014: Tu3D.3.

[26] Okamoto K. Fundamentals of optical waveguides［M］. Tokyo: Corona Publishing, 1992: 5-18.