论文标题
直接通过自相关测量直接确定超短laguerre-gauss脉冲的轨道角动量
Directly determining orbital angular momentum of ultrashort Laguerre-Gauss pulses via autocorrelation measurement
论文作者
论文摘要
基于第二次谐波生成（SHG）的自相关测量是测量超短脉冲时间持续时间的最著名技术，可以追溯到超快激光器的诞生。在这里，我们提出并在实验上证明了这种公认的技术也可以用于测量超短laguerre-gauss（LG）脉冲的轨道角动量。通过分析SHG信号的远场模式，明确确定了超短LG脉冲的完整空间结构，包括方位角和径向指标。我们的结果通过扩展其在激光表征方面的全部潜力，尤其是结构化的超静脉脉冲，为建立良好的自相关技术提供了重要的进步。
Autocorrelation measurement based on second-harmonic generation (SHG), the best-known technique for measuring the temporal duration of ultrashort pulses, could date back to the birth of ultrafast lasers. Here, we propose and experimentally demonstrate that such well-established technique can also be used to measure the orbital angular momentum of ultrashort Laguerre-Gauss (LG) pulses. By analysing the far-field pattern of the SHG signal, the full spatial structure of ultrashort LG pulses, including both azimuthal and radial indices, are unambiguously determined. Our results provide an important advancement for the well-established autocorrelation technique by extending it to reach its full potential in laser characterization, especially for structured ultrashort pulses.
