A tunable self-seeded Brillouin/erbium fiber laser utilizing an asymmetrical twin core fiber based Mach-Zehnder interferometer

A tunable self-seeded Brillouin/erbium fiber laser (BEFL) utilizing an asymmetrical twin core fiber based Mach-Zehnder interferometer (ATCF-MZI) is proposed and demonstrated. The proposed self-seeded BEFL has the advantage of being able to generate up to 17 output channels with high optical signal to noise ratio (> 10 dB). The Brillouin pump is self-seeded in the laser cavity instead of the extra Brillouin pumping. By bending the ATCF-MZI, an 8 nm wavelength-tunable range is achieved. This self-seeded BEFL shows linear tunability and good stability. Meanwhile, the experimental results indicate that the laser output with operation wavelength away from the free-running cavity mode has better output characteristics.