Sola Íñigo J, Alonso Benjamín
Grupo de Investigación en Aplicaciones del Láser y Fotónica, Departamento de Física Aplicada, University of Salamanca, 37008, Salamanca, Spain.
Sci Rep. 2020 Oct 27;10(1):18364. doi: 10.1038/s41598-020-75220-4.
In this work we firstly study the influence of different parameters in the temporal characterization of ultrashort laser pulses with the recently developed amplitude swing technique. In this technique, the relative amplitude of two delayed replicas is varied while measuring their second-harmonic spectra. Here we study the retrieval of noisy traces and the implications of having different delays or phase retardations (relative phases) between the two replicas. Then, we study the capability of the technique to characterize the pulses when the second-harmonic signal is spectrally uncalibrated or incomplete, presenting the analytical calculation of the marginal, which is used to calibrate the traces and to perform the pulse retrievals. We experimentally show the retrieval of different pulses using diverse delays and phase retardations to perform the amplitude swing trace and demonstrate that, from an uncalibrated trace, both the pulse information and the response of the nonlinear process can be simultaneously retrieved. In sum, the amplitude swing technique is shown to be very robust against experimental constraints and limitations, showing a high degree of soundness.
在这项工作中，我们首先利用最近开发的振幅摆动技术研究了不同参数对超短激光脉冲时间特性的影响。在该技术中，在测量两个延迟复制品的二次谐波光谱时，改变它们的相对振幅。在这里，我们研究了噪声迹线的检索以及两个复制品之间存在不同延迟或相位延迟（相对相位）的影响。然后，我们研究了在二次谐波信号光谱未校准或不完整时该技术表征脉冲的能力，给出了用于校准迹线和进行脉冲检索的边缘量的解析计算。我们通过实验展示了使用不同延迟和相位延迟进行振幅摆动迹线来检索不同脉冲，并证明从未校准的迹线中可以同时检索到脉冲信息和非线性过程的响应。总之，振幅摆动技术被证明对实验约束和限制具有很强的鲁棒性，表现出高度的可靠性。
