A self-similar mode locked fibre laser is studied based on a numerical model. By introducing a dimensionless factor k to characterize the pulse shape, the self-similar pulse evolution, formation and the temporal and s...A self-similar mode locked fibre laser is studied based on a numerical model. By introducing a dimensionless factor k to characterize the pulse shape, the self-similar pulse evolution, formation and the temporal and spectral shape changes due to the elements in the cavity are investigated throughout the laser cavity. The results show that in the self-similar mode locked fibre laser, self-similar pulse is first formed in the single-mode fibre, which is then amplified in the gain fibre. Gain bandwidth has a small influence on pulse shape, so high energy self-similar pulse can be obtained after amplification. Because net cavity dispersion directly influences the pulse width as well as peak power after compression by a pair of gratings, which can determine the pulse self-similar evolution, it is very important to control the net cavity dispersion to a certain range to obtain self-similar pulses.展开更多
We experimentally demonstrate an S-band double-pass （DP） discrete fibre Raman amplifier （FRA） gain-flattened by using a mechanically induced long-period fibre grating （LPFG）. Due to a photo-elastic effect in the...We experimentally demonstrate an S-band double-pass （DP） discrete fibre Raman amplifier （FRA） gain-flattened by using a mechanically induced long-period fibre grating （LPFG）. Due to a photo-elastic effect in the fibre and its peak loss, the wavelength and depth of the mechanically induced LPFG are continuously regulated by varying the pressures, the angle of the fibre on the graphite rods which are used to produce the periodical pressures along the fibre, the number and the diameter of the graphite rods. Using this gain flattening filter, the gain profile of the DP-FRA is flattened to within ±0.8 dB in the wavelength range from 1485 nm to 1525 nm.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 60677013, and the Doctoral Program Foundation of Institute of Higher Education of China under Grant No 20060055021.
文摘A self-similar mode locked fibre laser is studied based on a numerical model. By introducing a dimensionless factor k to characterize the pulse shape, the self-similar pulse evolution, formation and the temporal and spectral shape changes due to the elements in the cavity are investigated throughout the laser cavity. The results show that in the self-similar mode locked fibre laser, self-similar pulse is first formed in the single-mode fibre, which is then amplified in the gain fibre. Gain bandwidth has a small influence on pulse shape, so high energy self-similar pulse can be obtained after amplification. Because net cavity dispersion directly influences the pulse width as well as peak power after compression by a pair of gratings, which can determine the pulse self-similar evolution, it is very important to control the net cavity dispersion to a certain range to obtain self-similar pulses.
文摘We experimentally demonstrate an S-band double-pass （DP） discrete fibre Raman amplifier （FRA） gain-flattened by using a mechanically induced long-period fibre grating （LPFG）. Due to a photo-elastic effect in the fibre and its peak loss, the wavelength and depth of the mechanically induced LPFG are continuously regulated by varying the pressures, the angle of the fibre on the graphite rods which are used to produce the periodical pressures along the fibre, the number and the diameter of the graphite rods. Using this gain flattening filter, the gain profile of the DP-FRA is flattened to within ±0.8 dB in the wavelength range from 1485 nm to 1525 nm.
