The transmission characteristics of phase modulation pulse transmitted through the filter in the power amplifier are investigated theoretically and experimentally.The narrow bandpass filter can induce large temporal m...The transmission characteristics of phase modulation pulse transmitted through the filter in the power amplifier are investigated theoretically and experimentally.The narrow bandpass filter can induce large temporal modula-tion depth for the phase modulation pulse and induce double amplitude modulation(AM)if the frequency shift is lower than half bandwidth of the signal spectrum.We should choose a wider bandwidth filter to minimize the impact of the filter on the output pulse and suppress the amplified spontaneous emission(ASE)for the power fiber amplifier.These results are of benefit to the design of the fiber front end system.展开更多
In order to improve the signal-to-noise ratio of an all-fiber front-end system for high-energy pete-watt(PW)laser devices,we propose a method to restrain the noise by optical Kerr effect.In terms of analytical calcula...In order to improve the signal-to-noise ratio of an all-fiber front-end system for high-energy pete-watt(PW)laser devices,we propose a method to restrain the noise by optical Kerr effect.In terms of analytical calculation,it is found that the signal-to-noise ratio can be increased by three orders of magnitude with the cell of pulse cleaning for the pulses,with the full width at half maximum TFWHM larger than 100ps.However,numerical calculation indicates that the group-velocity dispersion(GVD)may have a marked effect on the pulses with TFWHM smaller than 100 ps but larger than 5ps,with the help of self-phase modulation(SPM).This would debase the performance of the cell of pulse cleaning.Meanwhile,we study the methods of restraining the distortion for the pulses with different peak powers to improve the performance of an all-fiber front-end system for high-energy PW laser devices,These results are of benefit to the experiments and the improvement of signal-to-noise ratio for high-energy PW laser devices.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 60878058the National Key Laboratory of Laser Fusion under Grant No 9140C6803010905.
文摘The transmission characteristics of phase modulation pulse transmitted through the filter in the power amplifier are investigated theoretically and experimentally.The narrow bandpass filter can induce large temporal modula-tion depth for the phase modulation pulse and induce double amplitude modulation(AM)if the frequency shift is lower than half bandwidth of the signal spectrum.We should choose a wider bandwidth filter to minimize the impact of the filter on the output pulse and suppress the amplified spontaneous emission(ASE)for the power fiber amplifier.These results are of benefit to the design of the fiber front end system.
基金Supported by the National Key Laboratory of Laser Fusion under Grant No 9140C6803010905.
文摘In order to improve the signal-to-noise ratio of an all-fiber front-end system for high-energy pete-watt(PW)laser devices,we propose a method to restrain the noise by optical Kerr effect.In terms of analytical calculation,it is found that the signal-to-noise ratio can be increased by three orders of magnitude with the cell of pulse cleaning for the pulses,with the full width at half maximum TFWHM larger than 100ps.However,numerical calculation indicates that the group-velocity dispersion(GVD)may have a marked effect on the pulses with TFWHM smaller than 100 ps but larger than 5ps,with the help of self-phase modulation(SPM).This would debase the performance of the cell of pulse cleaning.Meanwhile,we study the methods of restraining the distortion for the pulses with different peak powers to improve the performance of an all-fiber front-end system for high-energy PW laser devices,These results are of benefit to the experiments and the improvement of signal-to-noise ratio for high-energy PW laser devices.
