[1] [1] NAKAZAWA M,YOSHIDA E,KIMURA Y.Low threshold,290 fs erbium-doped fiber laser with a nonlinear amplifying loop mirror pumped by InGaAsP laser diodes[J].Appl Phy Lett,1991,59(17):2073-2075.

[4] [4] CAUTAERTS V,RICHARDSON D J,PASCHOTTA R,et al.Stretched pulse Yb3+:silica fiber laser[J].Opt Lett,1997,22(5):316-318.

[5] [5] NOSKE D U,TAYLOR J R.Spectral and temporal stabilisation of a diode-pumped ytterbium-erbium fiber soliton laser[J].Electr Lett,1993,29(25):2200-2202.

[6] [6] TSUN T O,ISLAM M K,CHU P L.High-energy femtosecond figure-eight fiber laser[J].Opt Commun,1997,141(1-2):65-68.

[7] [7] JEON M Y,LEE H K,AHN J T,et al.Wideband wavelength tunable modelocked fiber laser over 1557-1607 nm[J].Electr Lett,2000,36(4):300-302.

[10] [10] ZHAN L,WANG P H,GU Z C,et al.Amplitude-equalized high-order arbitrary numerator rational harmonic modelocked pulse generation in fiber-ring lasers using nonlinear polarization rotation[J].Opt Exp,2005,13(3):836-841.