K. Takenaga

Large-effective-area ten-core fiber with cladding diameter of about 200 μm

A multicore fiber with two-pitch layout is proposed to overcome the trade-off between core number and a cladding diameter of a standard hexagonal layout with a single-core pitch. A fabricated ten-core fiber simultaneously realizes effective area of about 120 μm(2) at 1550 nm, small crosstalk, and cladding diameter of 204 μm. The crosstalk between the center core and outer cores is about 30 dB smaller than that between outer cores. The small crosstalk of the center core would help to keep the transmission quality of the center core at the same level as that of the outer cores.

A large effective area few-mode multi-core fiber

A design concept of few-mode multi-core fiber is presented. A four-core fiber that supports two LP modes with large effective area (A_eff) larger than 110 μm² realizes the highest relative core multiplicity factor of 11.7.

Multicore fibre-based mode multiplexer/demultiplexer for three-mode operation of LP 01 , LP 11a , and LP 11b

A mode multiplexer/demultiplexer with a fused-fibre fan-in/fan-out device for three-mode operation of LP₀₁, LP_11a, and LP_11b is demonstrated using a partially elongated multi-core fibre. A fabricated mode multiplexer/demultiplexer exhibited a coupling efficiency greater than 79% over the C band.

Remotely pumped multicore erbium-doped fiber amplifier system with high pumping efficiency

We have experimentally clarified the optical amplification characteristics of a remotely pumped multicore erbium-doped fiber amplifier system. The pumping efficiencies of the system are ~4 times higher than those of the distributed Raman amplification system.

Quasi-single-mode homogeneous 31-core fibre

A homogeneous 31-core fibre with a cladding diameter of 230 μm for quasi-single-mode transmission is designed and fabricated. LP01-crosstalk of -38.4 dB/11 km at 1550 nm is achieved by using few-mode trench-assisted cores.

Multicore fiber with ring structure

The characteristics of MCFs with one-ring structure are reviewed. The MCFs realize the number of cores larger than 10, suppressed crosstalk and enlarged Aeff under limited cladding diameter in terms of mechanical reliability.

Low-loss fusion splice technique for multicore fiber with a large cladding diameter

Fusion splice technique for multicore fiber was demonstrated. Low splice loss less than 0.1 dB in average was realized by using end-view alignment system and swing electrode system under small cleaved angle condition.

High core count single-mode multicore fiber for dense space division multiplexing

Multicore fibers and few-mode fibers have the potential to realize dense-space-division multiplexing systems. Several dense-space-division multiplexing system transmission experiments over multicore fibers and few-mode fibers have been demonstrated so far. Multicore fibers, including recent results by our group, are reviewed in this paper.

Bend sensitive wavelength filtering in concentric core solid photonic bandgap fibre

Bend sensitive wavelength filtering property in a concentric core solid photonic bandgap fibre is resented. The property is realised by not only the bandgap effect but mode coupling between the core mode and ring modes.

Accuracy of Core Alignment with End-View Function for Multicore Fiber

Passive and automatic core alignment of MCFs with an end-view function is demonstrated. It is confirmed that the accuracy of the end-view alignment method is feasible for fusion splicing of MCFs.