He Yanqing, He Lixin, Wang Pu, Wang Bincheng, Sun Siqi, Liu Ruxuan, Wang Baoning, Lan Pengfei, Lu Peixiang
Opt Express. 2020 Jul 6;28(14):21182-21191. doi: 10.1364/OE.397560.
We demonstrate a method to simultaneously measure the rotational temperature and pump intensity in laser-induced molecular alignment by the time-resolved high harmonic spectroscopy (HHS). It relies on the sensitive dependence of the arising times of the local minima and maxima of the harmonic yields at the rotational revivals on the pump intensity and rotational temperature. By measuring the arising times of these local extrema from the time-resolved harmonic signals, the rotational temperature and pump intensity can be accurately measured. We have demonstrated our method using N molecules. The validity and robustness of our method are tested with different harmonic orders and by changing the gas pressures as well as the distance between the gas exit and the optical axis. Moreover, we have also demonstrated the versatility of our method by applying it to CO molecules.
我们展示了一种通过时间分辨高谐波光谱法（HHS）同时测量激光诱导分子取向中的转动温度和泵浦强度的方法。它依赖于在转动复兴时谐波产率的局部最小值和最大值的出现时间对泵浦强度和转动温度的敏感依赖性。通过从时间分辨谐波信号中测量这些局部极值的出现时间，可以准确测量转动温度和泵浦强度。我们使用N分子演示了我们的方法。我们的方法的有效性和稳健性通过不同的谐波阶数以及改变气体压力和气体出口与光轴之间的距离进行了测试。此外，我们还通过将其应用于CO分子展示了我们方法的通用性。
