Pressure measurements using hybrid femtosecond/picosecond rotational coherent anti-Stokes Raman scattering.
Pressure measurements using hybrid femtosecond/picosecond rotational coherent anti-Stokes Raman scattering.
复制标题
使用混合飞秒/皮秒旋转相干反斯托克斯拉曼散射进行压力测量。
作者：
S. Kearney;P. Danehy
我们研究了用fs/ps旋转CARS测量气相压力的可行性。飞秒泵浦和斯托克斯脉冲脉冲制备旋转拉曼相干，这是由拉曼制备的时间延迟引入的5-ps高能脉冲探测的。这些超快激光脉冲比碰撞减相时间尺度短，从而实现了一种新的混合时频域压力检测方案。在室温气体池中，在压力为0.4 ~ 3atm，探针延迟为16 ~ 298 ps的条件下，记录了氮气的单激光旋转CARS光谱，并研究了压力数据的准确性和精度对探针延迟的敏感性。与以前的激光诊断压力测量相比，该技术具有卓越的精度和相当的准确性。
We investigate the feasibility of gas-phase pressure measurements using fs/ps rotational CARS. Femtosecond pump and Stokes pulses impulsively prepare a rotational Raman coherence, which is probed by a high-energy 5-ps pulse introduced at a time delay from the Raman preparation. These ultrafast laser pulses are shorter than collisional-dephasing time scales, enabling a new hybrid time- and frequency-domain detection scheme for pressure. Single-laser-shot rotational CARS spectra were recorded from N2 contained in a room-temperature gas cell for pressures from 0.4 to 3 atm and probe delays ranging from 16 to 298 ps. Sensitivity of the accuracy and precision of the pressure data to probe delay was investigated. The technique exhibits superior precision and comparable accuracy to previous laser-diagnostic pressure measurements.