Abstract
We demonstrate a self-seeded multi-wavelength Brillouin–erbium fibre laser with double Brillouin frequency gap. The twice channel gap is induced by the gain difference in different directions. Thirty-six stable output channels with 20 GHz frequency gap are obtained when the 980 nm pump power is 300 mW. The factor that induces the double frequency gap is investigated and proved.
Acknowledgements
The authors gratefully acknowledge support from National Nature Science Foundation of China [No. 61378090, 60925019, 61090393 and 61177036], Science and Technology Innovation Team of Sichuan Province [No. 2011JTD0001] and the Fundamental Research Funds for the Central Universities [Project No. ZYGX2012J064].