Modeling the optical gain and noise in the bent Er³⁺-doped LiNbO 3 waveguide of the Mach-Zehnder interferometer

Abstract

Er -dopedis widely used for the fabrication of integrated optic components. In the small gain approximation and the unsaturated regime in this paper we report some original results in the evaluation ofthe spectral optical gain and spectral noise figure in the bent Er3 -doped waveguide ofthe Mach-Zehnder interferometer pumped near 1484 nm using erfc, Gaussian and constant profile of the Er ions in crystal. We used a quasi-two-level model to simulate the optical amplification in Er -doped straight and bent waveguide amplifiers and we demonstrated that rather high gains (-1.1 dB) and low noise figures (-3 .3 dB) at the end of the bent arm of the Mach-Zehnder interferometer are achievable for 100 mW input pump power. The obtained results can be used for the design ofthe integrated Mach-Zehnder interferometers and optic devices.