We numerically investigate the energy and arrival-time noise of ultrashort laser pulses produced via resonant dispersive wave (RDW) emission in gas-filled hollow-core waveguides under the influence of pump-laser instability. We find that for low pump energy, fluctuations in the pump energy are strongly amplified. However, when the generation process is saturated, the energy of the RDW can be significantly less noisy than that of the pump pulse. This holds for a variety of generation conditions and while still producing few-femtosecond pulses. We further find that the arrival-time jitter of the generated pulse remains well below one femtosecond even for a conservative estimate of the pump pulse energy noise, and that photoionisation and plasma dynamics can lead to exceptional stability for some generation conditions. By applying our analysis to a scaled-down system, we demonstrate that our results hold for frequency conversion schemes based on both small-core microstructured fibre and large-core hollow capillary fibre.

我们数值研究了在泵浦激光器不稳定性的影响下，在充气空心波导中通过共振色散波 (RDW) 发射产生的超短激光脉冲的能量和到达时间噪声。我们发现，对于低泵浦能量，泵浦能量的波动被强烈放大。然而，当生成过程饱和时，RDW 的能量可以明显低于泵浦脉冲的能量。这适用于各种生成条件，同时仍会产生少量飞秒脉冲。我们进一步发现，即使对泵浦脉冲能量噪声进行保守估计，所产生脉冲的到达时间抖动仍远低于 1 飞秒，并且光电离和等离子体动力学可以导致某些产生条件的异常稳定性。