[1] Sun Y, Sulhoff J W, Srivastava A K, et al. 80 nm ultra-wideband erbium-doped silica fiber amplifier [J]. Electron.Lett., 1997, 33(23): 1965-1967.
[2] Nilsson J, Sun S Y, Hwang S T, et al. Long-wavelength erbium-doped fiber amplifier gain enhanced by ASE end-reflectors [J]. IEEE Photon. Technol. Lett., 1998, 10(11): 1551-1553.
[3] Lee J, Ryu U C, Ahn S J, et al. Enhancement of power conversion efficiency for an L-band EDFA with a secondary pumping effect in the unpumped EDF section [J]. IEEE Photon. Technol. Lett., 1999, 11(1): 42-44.
[4] Mahdi M A, Ahmad H. Gain enhanced L-band Er3+-doped fiber amplifier utilizing unwanted backward ASE [J].IEEE Photon. Technol. Lett., 2001, 13(10): 1067-1069.
[5] Yeniay A, Gao Renyuan. Single stage high power L-band EDFA with multiple C-band seeds [C] ∥ OFC 2002,ThJ2, 457-458.
[6] Meng Hongyun, Liu Yange, Gao Weiqing, et al. Reflection L-band erbium-doped fiber amplifier based fiber loop mirror [J]. Microwave and Optical Technology Lett., 2003, 36(6): 501-503.
[7] Mao Qinghe, John W Y Lit. Amplification enhancement of L-band erbium-doped fiber amplifiers by reflection scheme [J]. Optics Communications, 2002, 201: 61-69.