无干扰混合 fs/ps 振动 CARS 高温火焰测温法。

Interference-free hybrid fs/ps vibrational CARS thermometry in high-pressure flames.

出版信息

Opt Lett. 2018 Oct 15;43(20):4911-4914. doi: 10.1364/OL.43.004911.

DOI:10.1364/OL.43.004911

PMID:30320781

Abstract

Interference-free hybrid femtosecond/picosecond vibrational coherent anti-Stokes Raman scattering (CARS) of nitrogen is reported for temperature measurements of 1300-2300 K in high-pressure, laminar H-air and CH-air diffusion flames up to 10 bar. Following coherent Raman excitation by 100 fs duration pump and Stokes pulses, a time-asymmetric probe pulse is used for the detection of spectrally resolved N CARS signals at probe delays as early as ∼200-300 fs. This allows for full rejection of nonresonant contributions while being independent of collisions for single-shot precision of ±2% at elevated pressures. The effects of collisions at longer probe-pulse delays are also investigated to determine the feasibility of varying the detection timing from 200 fs to 100 ps.

摘要

报道了氮的无干扰混合飞秒/皮秒振动相干反斯托克斯拉曼散射（CARS），用于在 1000-2300 K 的温度范围内测量高达 10 巴的高压层流 H 空气和 CH 空气扩散火焰。在由 100 fs 持续时间的泵浦和斯托克斯脉冲进行相干拉曼激发后，使用时间不对称的探测脉冲探测光谱分辨的 N CARS 信号，探测延迟时间最早可达约 200-300 fs。这允许完全消除非共振贡献，同时在高压下对单次精度的影响独立于碰撞，精度为 ±2%。还研究了较长探测脉冲延迟的碰撞影响，以确定从 200 fs 到 100 ps 改变检测时间的可行性。