Design and fabrication of ultra-low crosstalk and low-loss multi-core fiber: erratum.

This erratum amends typographical errors in Eq. (1) and Table 2Table 2Optical properties of each core of the fabricated MCF.Attenuation [dB/km]MFD [µm]Aeff [µm2]λcc [nm]CD [ps/nm/km]D.

Effective area measurement of few-mode fiber using far field scan technique with Hankel transform generalized for circularly-asymmetric mode.

We report on a measurement method for the effective area of the few-mode fiber. We derived a transform equation between a near-field pattern and a far-field pattern generalized for circularly-asymmetric higher-order modes of a cylindrical core, and enabled effective area measurement of the higher-order modes using high-dynamic-range far-field scan technique and low-crosstalk mode multiplexer. The measured effective area values agreed well with the values that were numerically predicted using a finite-element method from the refractive index profile, when the modal crosstalk was suppressed.

Temperature response of an all-solid photonic bandgap fiber for sensing applications.

The spectral shift due to temperature in the photonic bandgap (PBG) of an all-solid PBG fiber is investigated, aiming at discrete and distributed temperature sensing. A temperature rise induces a red shift in the bandgap spectra, which can be easily and precisely monitored by measuring the fiber transmission near one of the band edges. Two different situations that are potentially compatible with distributed and quasi-distributed sensing were investigated: heating a 2 m section of a longer (~10 m) fiber, and heating the whole extension of a fiber that is tens of centimeters in length and was spliced to conventional fibers on both sides.

Uncoupled multi-core fiber enhancing signal-to-noise ratio.

We designed and fabricated a low-crosstalk seven-core fiber with transmission losses of 0.17 dB/km or lower, effective areas larger than 120 μm(2), and a total mean crosstalk to the center core of -53 dB after 6.99-km propagation (equivalent to -42.

Design and fabrication of ultra-low crosstalk and low-loss multi-core fiber.

We designed and fabricated a multi-core fiber (MCF) in which seven identical trench-assisted pure-silica cores were arranged hexagonally. To design MCF, the relation among the crosstalk, fiber parameters, and fiber bend was derived using a new approximation model based on the coupled-mode theory with the equivalent index model. The mean values of the statistical distributions of the crosstalk were observed to be extremely low and estimated to be less than -30 dB even after 10,000-km propagation because of the trench-assisted cores and utilization of the fiber bend.