Experimental investigation on environmental stability of erbium-doped fiber laser based on Sagnac interferometer with a polarization-maintaining photonic crystal fiber

A tunable single- and dual-wavelength erbium-doped fiber laser (EDFL) based on Sagnac interferometer (SI) with a polarization-maintaining photonic crystal fiber (PMPCF) is built. The stability of lasing output under different environmental factors including temperature, pressure and strain has been experimentally investigated by comparing with traditional PMF based EDFL. The measured single-wavelength shift in response of temperature is 0.01 nm/°C which is seven times smaller than that of traditional PMF based EDFL and the pressure sensitivity is 0.04 nm/N which is almost one order of magnitude smaller than that of traditional PMF-SI based EDFL. Besides, the wavelength stability is still well maintained under external strain. Experimental results indicate that the introduction of PMPCF can be helpful to develop high stability EDFL for rough environment.