Temperature tuning of superluminescent Er³⁺-doped source based on Mach–Zehnder interferometer and long-period fiber gratings

The simulation and experimental results of the temperature tuning of an Er3+-doped fiber (EDF) Mach–Zehnder interferometer (MZI) proposed for sensing applications were presented. The MZI was mechanically induced using two polypropylene long-period fiber gratings made with a pulsed CO2 laser. The proposed interferometer device showed four peaks of transmittance and multifiltering around the 1550-nm region, suitable for Telecomm systems. The numerical simulation is simple and is based on rate equations which allows for amplified spontaneous emission behavior prediction and mode propagation. The demonstrated fringe pattern makes the proposed device suitable for multiwavelength sensors based on EDFs.