We experimentally examined the propagation of a Gaussian-shaped temporal pulse through a serial array of ring resonators, truncating the pulse before its peak. We observed the process whereby a smooth pulse peak related to the Gaussian pulse emerged even when the incident pulse was truncated before its peak, as the pulse passed through an increasing number of ring resonators. The peak emerged when the negative group delay accumulated beyond the pulse truncation time point. This result demonstrated that the earlier portion of the input pulse envelope developed into a smooth Gaussian-shaped pulse peak in the superluminal pulse in good agreement with the analyses based on the instantaneous spectrum. We also discussed the propagation of truncated pulses in a slow light system, where the peak disappeared in the output pulse despite the peak in the input pulse.

中文翻译：

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在高Q环形谐振器的串行阵列中从峰值截断的高斯光脉冲产生脉冲峰值

我们通过实验检查了高斯形时间脉冲通过环形谐振器串行阵列的传播，并在脉冲达到峰值之前将其截断。我们观察到这样的过程：随着脉冲穿过越来越多的环形谐振器，即使入射脉冲在其峰值之前被截断，与高斯脉冲相关的平滑脉冲峰值也会出现。当负群延迟累积超过脉冲截断时间点时，出现峰值。该结果表明，与基于瞬时频谱的分析相吻合，输入脉冲包络的较早部分在超光脉冲中发展成为平滑的高斯型脉冲峰。我们还讨论了慢脉冲系统中截断脉冲的传播，