为了精确地测量阿秒脉冲的特性,自主研制了一套具有高能量分辨率的阿秒条纹相机,该相机采用了电子飞行距离长达2 m的磁瓶式结构电子飞行时间谱仪,可在提高能量分辨率的同时具有较高的光电子收集效率;在该设备的光路系统中实现了NIR飞秒脉冲与XUV阿秒脉冲延时扫描的稳定精度<20 as(均方根)。实验中采用双光选通门技术整形飞秒脉冲的光电场,在氖气池中产生了孤立阿秒脉冲。利用上述阿秒条纹相机测量该脉冲,获得了阿秒光电子条纹谱,通过基于单频滤波的相位重构算法得到159 as的孤立阿秒脉冲。

In order to accurately measure the characteristics of attosecond pulses, we have independently developed a set of attosecond streaking camera with high energy resolution. The device adopts an electronic time-of-flight spectrometer with a magnetic bottle structure and an electronic flight distance of up to 2 m. Based on the above design, the spectrometer has high energy resolution and collection efficiency. The stability accuracy of delayed scanning of NIR femtosecond pulses and XUV attosecond pulses is smaller than 20 as (root-mean-square) in optical system of the device. A double optical gating technology was used to shape the optical electric field of the femtosecond pulses, and an isolated attosecond pulse was generated in the Ne gas cell. The attosecond streaking spectrogram was obtained by the attosecond streaking camera. An isolated 159-as attosecond pulse was achieved through phase retrieval by omega oscillation filtering (PROOF).