A simple tunable multiwavelength Brillouin-erbium fiber ring laser with low threshold power

A simple tunable multiwavelength Brillouin-erbium fiber ring laser based on a 10 m common erbium-doped fiber and a 3 km single mode fiber is presented. The simple ring cavity consists of only three optical components. One 3 dB optical coupler is used as input and output coupling and this configuration reduces the insertion loss and complexity of the fiber laser. The fiber laser provides a low threshold power of 5 mW and a tuning range of 25 nm at the Brillouin pump power of 6 dBm and the 1480 nm pump power of 10 mW. With the maximum 1480 nm pump power of 110 mW, 21 average output channels with 0.084 nm channel spacing and 13 nm tuning range are achieved.