Wavelength flattened saturated erbium amplifier using multiple side-tap Bragg gratings

Abstract

By writing several loss-inducing photosensitive side-tap Bragg gratings in a short length of optical fibre, the gain variation of ±1.6 dB over a bandwidth of 33 nm in a saturated erbium doped fibre amplifier is reduced to ±0.3 dB. It is shown for the first time that these gratings may be written with predictable ease.