Novel multi-core fibers for mode division multiplexing: proposal and design principle

Abstract

Abstract:We propose a new type of optical fiber called homogeneous multi-core fiber (MCF) to drastically increase the transmission capacity of single fiber using the mode-division multiplexing. In this MCF, identical cores are closely arranged so that the cores are strongly coupled to each other to form coupled modes, each of which corresponds to a transmission channel. A novel mode multi/demultiplexer is proposed to discriminate each coupled mode. To rearrange cores to match the mode multi/demultiplexer, a hybrid configuration of coupled homogeneous with uncoupled heterogeneous multi-core is proposed. An example of hybrid configuration is designed so that the cross-talk becomes sufficiently small. Keywords: multi-core fiber, coupled mode, mode division multiplexing Classification: Optical fiber IEICE Electron. Exp., vol. 6, no. 2, pp. 98-103, Feb. 2009 References

Multicore fibers for large capacity transmission

“…On the other hand, in the coupled MCFs, several cores are placed to strongly and/or weakly couple between each other. Coupled MCFs supporting single transverse mode and multi transverse modes have been investigated for high power fiber laser applications [9,10], since they are able to be used as large-mode-area (LMA) fibers, while the coupled MCFs supporting a few supermodes can be used as few-mode fibers (FMFs) for large capacity transmission experiments with mode-division multiplexing (MDM) technique [11][12][13][14]. In terms of core arrangement in uncoupled MCFs, homogeneous MCFs with identical multiple cores [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] and heterogeneous MCFs with several kinds of different cores [31][32][33][34][35] have been reported.…”

“…The combination of multicore and few-mode, FM-MCF, is also another candidate for SDM. The concept of an FM-MCF has already been proposed a few years ago [7,11] and fabrication results have been demonstrated recently [36][37][38][39][40][41]. In addition, a hybrid MCF that involves single-mode cores and few-mode cores has been used in a transmission experiment that recorded 1.05 Pb/s/fiber on a 3-km hybrid MCF [42].…”

“…A eff at 1550 nm of LP 01 mode and LP 11 core-to-core crosstalk between LP 01 mode and LP 01 mode, between LP 01 mode and LP 11 mode, and between LP 11 mode and LP 11 mode, respectively. XT is about 40-dB larger than XT 01-01 .…”

Serial branching mode multi/demultiplexer for homogeneous multi-core fibers

“…The orthogonal eigenmodes in a fiber are utilized as independent transmission channels in the MDM scheme. Thus far, to realize the MDM transmission, several novel optical fibers have been proposed such as the few-mode fiber (FMF) [2,3,4] which supports several modes by expanding the core diameter and strongly coupled multicore fiber (MCF) [5,6] which utilizes coupled modes supported in coupled single mode cores as independent transmission channels. On the other hand, weakly coupled MCFs have been proposed and demonstrated [7,8] to reduce the difference of group delay between coupled modes.…”

“…On the other hand, weakly coupled MCFs have been proposed and demonstrated [7,8] to reduce the difference of group delay between coupled modes. As the strongly coupled MCF [5,6], we have proposed and demonstrated a novel coupled MCF, named homogeneous coupled MCF, which supports strongly coupled modes by arranging several identical single mode cores close to each other.…”