Simulation of wide wavelength tuning of As2Se3 π-PSFBG narrow band fiber laser based on temperature and strain

Abstract

In this work, the temperature (strain) properties of As2Se3 π-phase-shift fiber Bragg gratings (π-PSFBGs) are numerically investigated. The sensing sensitivities are 0.0665 nm °C−1 (0.8598 pm μϵ −1) at 1.55 μm, 0.1546 nm °C−1 (1.9968 pm μϵ −1) at 3.6 μm, 0.2717 nm °C−1 (3.51 pm μϵ −1) at 6.328 μm, and 0.4551 nm °C−1 (5.8796 pm μϵ −1) at 10.6 μm, and the sensitivities are improved with the increasing Bragg wavelength. Based on them, a high-performance narrow band fiber laser is theoretically proposed. The proposed tunable laser has a wider wavelength adjustment range in mid-infrared region, which can reach 27.306 nm at around 10.6 μm. Moreover, the obvious Bragg wavelength shift induced by stretching the As2Se3 π-PSFBG helps widen the tunable range of the laser, making possible a fine tuning. Being simple in structure and high in sensitivity, the proposed laser can be applied in mid-infrared region, which is the fingerprint region of numerous molecules and which closely relates to military aviation, environmental conservation, biology and health care regions.