H. Masuda et al., WIDE-BAND, GAIN-FLATTENED, ERBIUM-DOPED FIBER AMPLIFIERS WITH 3 DB BANDWIDTHS OF GREATER-THAN-50NM, Electronics Letters, 33(12), 1997, pp. 1070-1072
3dB bandwidths of 52nm (1556-1608nm) for a silicate erbium-doped fibre
amplifier (EDFA) and 50nm (1554-1604nm) for a fluoride EDFA have been
obtained by a novel scheme with two-state erbium-doped fibres and an
intermediate equaliser. Low noise figures and high pump efficiencies o
f the EDFAs have been confirmed.