Optical fiber communication 22021/2/19 A. The discreet states of isolated erbium ions are broadened into bands by inhomogeneous stark splitting. B The distribution of company within the bands is thermal CThe net effect is amplification between 1525 and 1570nm, but the gain is not flat.1-2 Copyright Wang Yan 2021/2/19 Optical fiber communications A.The discreet states of isolated erbium ions are broadened into bands by inhomogeneous stark splitting. B.The distribution of company within the bands is thermal. C.The net effect is amplification between 1525 and 1570nm,but the gain is not flat