Er3+/Yb3+ co-doped all-fiber Mach-Zehnder interferometer for 1550nm applications

In this work an Er3+/Yb3+ co-doped all-fiber Mach-Zehnder interferometer that could be suitable for telecomm channel selection, temperature sensing or torsion sensing applications is proposed. The experimental array consists of a 980nm pump laser diode at 350mW output power, a 30cm co-doped fiber segment from our own design, and a mechanically-induced long period fiber grating in cascade with a tapered section, both on the co-doped fiber. The experimental results show an ASE operation bandwidth spectrum from 1450nm to 1650nm. The resulting interference pattern line-width is around 10nm with a 0.5dBm depth. The theoretical model based on Einsteins rate equations, along with the LPG in-house fabrication method, and full experimental results are explained.