Gain and noise characteristics of phosphate glass \(\hbox {Er}^{3+}\)\(\hbox {Yb}^{3+}\) co-doped waveguide amplifiers
Under the conditions of the uniform doping and the steady state, simulation is performed for the phosphate glass \(\hbox {Er}^{3+}\)\(\hbox {Yb}^{3+}\) co-doped waveguide amplifier by using a formulized iteration method to solve the rate equations and the propagation equations. In the simulation, we have considered ion-ion interaction mechanisms including upconversion, cross-relaxation, non-radiation relaxation, and energy transduction between \(\hbox {Yb}^{3+}\) and \(\hbox {Er}^{3+}\) ions, as well as the amplified spontaneous emission along the positive and negative directions of the waveguide. The gain and noise characteristics of the device are analyzed and discussed, and some useful results are obtained in three kinds of pump schemes, i.e. the forward-, backward- and bidirectional pump schemes. Simulation results show that by selecting proper parameter values, the output gain can be achieved over 10.3dB, and the noise figure can be controlled below 3dB.
gain \(\hbox {er}^{3+}\)\(\hbox {yb}^{3+}\) co-doped waveguide amplifier pump scheme noise figure