Loop Erbium-Doped Fiber Amplifiers

A comprehensive study of implementing erbium-doped fiber amplifiers (EDFAs) using a loop configuration is presented. Two different schemes based on the mechanism of directing the loop output are investigated. The amplified spontaneous emission at the output port is 3 dB lower than conventional designs. This configuration is recommended for high-power EDFAs.     

Yb3+sensitized Er3+-doped waveguide amplifiers: a theoretical approach

Silicate and phosphate glass waveguide amplifiers doped with Er³⁺, and co-doped with Er³⁺/Yb³⁺ are theoretically studied. Configurations for core and core–cladding doped waveguide amplifiers are considered. It is shown that gain in the core–cladding doped amplifiers is considerably higher than core doped amplifiers. It is also shown that with input signal power up to 1 and 200mW pump power, a 12.5dB gain can be achieved in a 3cm long waveguide amplifier, with a noise figure of 3dB.     

Optical switching in a coupler with saturable nonlinearity

Abstact We report in this paper a numerical study of optical switching in couplers with saturable nonlinearity. Regions that characterize different coupling behaviour are revealed. It is shown that, in the presence of saturation, a Gaussian pulse should be used instead of solitons for negligible pulse splitting between the coupler arms. Nearly complete switching is possible depending on the input optical power and the index saturation parameter.