Highly Doped Erbium Fibers

Fibercore Limited has used the high-volume manufacturing techniques it has developed for the
supply of hundreds of kilometres of PM fiber into the fiber optic gyroscope industry, every
month, to introduce MetroGain™ - the most cost-effective erbium doped fiber on the market.
In addition to their low price, MetroGain™ 5 and MetroGain™ 12 deliver excellent
performance in 1 - 16 channel systems in terms of both conversion efficiency and noise figure
with > 70% (quantum) and < 5 dB achieved routinely in commercially-produced EDFAs.
MetroGain™ 5 has a typical gain-length of 8 - 14 metres and overall performance is relatively
insensitive to small changes in fiber length - simplifying EDFA manufacture. MetroGain™ 12,
on the other hand, not only provides the ultimate in cost-effectiveness, with typical gain-lengths
of 4 - 6 metres, but can also be configured to deliver excellent L-band performance1. This
exceptionally short gain-length, when combined with the optional 80 μm diameter, makes
MetroGain™ 12 perhaps the ultimate 'Metro' fiber.
Notes 1. L-band EDFAs require 30 - 40 m gain-lengths, depending on precise configuration

Simulation Software

MetroGain™ are supplied complete with a full set of modelling parameters to enable you to
both evaluate the products and to optimise your EDFA design without costly experimentation.
These parameters may be used in most of the proprietary software currently available on the
market. Alternatively, Fibercore Limited provides powerful and sophisticated simulation
software to all of its OEM customers, free of charge, enabling them to analyse a wide range of
system configurations and accurately predict EDFA performance.

MetroGain™
Order Code M-5/980/125

Cut-off Wavelength 900 - 970 nm
Numerical Aperture 0.22 - 0.24

Mode-Field Diameter2 3.5 μm (980 nm), 5.9 μm (1550 nm)
Absorption at Pump Wavelength 4.5 - 5.5 dB/m (980nm)

Proof-Test 1% or 2% (100 kpsi or 200 kpsi)
Background Loss5 < 10 dB/km

Fiber Diameter 125 ± 1 μm

Core Cladding Concentricity < 0.5 μm
Coating Diameter 245 μm (nominal)

Coating Type Dual Acrylate

Low cost
High conversion efficiency
Short or ultra-short gain-lengths
MetroGain™ 12 has excellent L-band capabilities
Broad spectrum ideal for ASE sources