Tunable spacing of O-band multiwavelength Brillouin fiber laser

Tunable spacing of O-band multi wavelength Brillouin fiber laser is demonstrated. The channel spacing is varied by employing two types of cavities. A full closed linear cavity produce multi wavelength Brillouin fiber laser with 12.5GHz while a ring cavity provide channel spacing of 25.0 GHz. By combining these two cavities and employing optical channel switch, the channel spacing are varied. The comparison of Brillouin threshold between O-band and C-band is demonstrated. In particular, an O-band transmission window is used instead of C-band due to its lower Brillouin threshold.