Line Shape Effects in the Operation of Thulium and Erbium Doped Fiber Amplifiers

Abstract

This work describes the effect of Gaussian line shape on the comparison of the amplification characteristics (gain) and the Noise figure (NF) of the Thulium and Erbium in the host materials which the Yttria Alumina-Silica glass. The gain using this host material covers the range 1.45-1.65 μm. Thulium-doped fiber amplifiers operated in the region of wavelength (14801510 nm) which is called S-band. The main pump source is 1.04 and 1.55 pm which creates population inversion between 3F4 (upper laser level) and 3H4 (lower laser level), and Erbium- doped fiber amplifiers operated in the region (1510-1650 nm) which is called L -band with the pump wavelength 980 nm. It is found that the erbium doped yttria-alumina silicate fiber amplifier exhibits a maximum gain of 40.3 dB at the central wavelength 1540 nm and minimum noise figure 14 dB, but the broadening in the gain curve is 20 nm. Also it is found that the thulium doped yttria-alumina silicate fiber amplifier exhibits a maximum gain of 27.5 dB at the central wavelength 1467 nm and minimum noise figure 2.5 dB, with the broadening in the gain curve is 41 nm. Gain flatness was investigated and the results strongly confirm the feasibility of using this hosts' glass doped with Thulium in practical ultra large capacity wavelength division multiplexing networks.