Higher-order nonlinear Schrodinger equation with the Hirota constraint conditions is considered, and an analytic solution, which can describe the modulational instability process, is presented. Based on the solution, ...Higher-order nonlinear Schrodinger equation with the Hirota constraint conditions is considered, and an analytic solution, which can describe the modulational instability process, is presented. Based on the solution, a new pulse train without continuous wave (CW) background is generated in quadratures and the propagation of the pulse train is discussed in detail by simulating numerically. The results show that, unlike the propagation of the picosecond pulse train, under the effects of the higher-order terms, the pulse train cannot propagate along the fibre when the energy is very high; however, for some medium energy the pulse train can stably propagate. We also investigate the stability of the pulse train against violation of the Hirota conditions, and the results show that the pulse train can still propagate stably when the Hirota conditions are broken.展开更多
We have experimentally studied the mode-locking dynamics of a polarization-maintaining figure-of-eight laser which has a semiconductor optical amplifier as gain medium. Self-starting mode-locking at the fundamental re...We have experimentally studied the mode-locking dynamics of a polarization-maintaining figure-of-eight laser which has a semiconductor optical amplifier as gain medium. Self-starting mode-locking at the fundamental repetition rate of 18 MHz is obtained at the lasing threshold, and further increasing the bias current leads to the progressive emission of additional optical pulses in each round trip and eventually to mode-locked emission at increasingly high harmonics of the fundamental repetition rate, up to 2.45 GHz. The intensity autocorrelation of the amplified mode-locked pulses has a full width at half-maximum duration of 382 fs, which corresponds to a pulse duration of 247 fs.展开更多
Narrow-band THz coherent Cherenkov radiation can be driven by a subpicosecond electron bunch trav- eling along the axis of a hollow cylindrical dielectric-lined waveguide. We present a scheme of compact THz radiation ...Narrow-band THz coherent Cherenkov radiation can be driven by a subpicosecond electron bunch trav- eling along the axis of a hollow cylindrical dielectric-lined waveguide. We present a scheme of compact THz radiation source based on the photocathode rf gun. On the basis of our analytic result, the subpicosecond electron bunch with high charge (800 pC) can be generated directly in the photocathode rf gun. According to the analytical and simulated results, a narrow emission spectrum peaked at 0.24 THz with 2 megawatt (MW) peak power is expected to gain in the proposed scheme (the length of the facility is about 1.2 m).展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 60477026).
文摘Higher-order nonlinear Schrodinger equation with the Hirota constraint conditions is considered, and an analytic solution, which can describe the modulational instability process, is presented. Based on the solution, a new pulse train without continuous wave (CW) background is generated in quadratures and the propagation of the pulse train is discussed in detail by simulating numerically. The results show that, unlike the propagation of the picosecond pulse train, under the effects of the higher-order terms, the pulse train cannot propagate along the fibre when the energy is very high; however, for some medium energy the pulse train can stably propagate. We also investigate the stability of the pulse train against violation of the Hirota conditions, and the results show that the pulse train can still propagate stably when the Hirota conditions are broken.
基金Ministerio de Economía y Competitividad(MINECO)(TEC2015-65212-C3-3-P)
文摘We have experimentally studied the mode-locking dynamics of a polarization-maintaining figure-of-eight laser which has a semiconductor optical amplifier as gain medium. Self-starting mode-locking at the fundamental repetition rate of 18 MHz is obtained at the lasing threshold, and further increasing the bias current leads to the progressive emission of additional optical pulses in each round trip and eventually to mode-locked emission at increasingly high harmonics of the fundamental repetition rate, up to 2.45 GHz. The intensity autocorrelation of the amplified mode-locked pulses has a full width at half-maximum duration of 382 fs, which corresponds to a pulse duration of 247 fs.
基金Supported by Chinese National Foundation of Natural Sciences(11205152,11375199)Fundamental Research Funds for the Central Universities(WK2310000042)Major State Basic Research Development Program of China(2011CB808301)
文摘Narrow-band THz coherent Cherenkov radiation can be driven by a subpicosecond electron bunch trav- eling along the axis of a hollow cylindrical dielectric-lined waveguide. We present a scheme of compact THz radiation source based on the photocathode rf gun. On the basis of our analytic result, the subpicosecond electron bunch with high charge (800 pC) can be generated directly in the photocathode rf gun. According to the analytical and simulated results, a narrow emission spectrum peaked at 0.24 THz with 2 megawatt (MW) peak power is expected to gain in the proposed scheme (the length of the facility is about 1.2 m).