Lehrstuhl für Technische Thermodynamik and Erlangen Graduate School in Advanced Optical Technologies(SAOT), Friedrich-Alexander-Universität Erlangen Nürnberg, Am Weichselgarten 8, D-91058, Erlangen, Germany.
Opt Lett. 2009 Dec 1;34(23):3755-7. doi: 10.1364/OL.34.003755.
Time-resolved pure-rotational coherent anti-Stokes Raman spectroscopy using picosecond-duration laser pulses is investigated for gas thermometry. The use of picosecond laser pulses significantly reduces background caused by scattering of the probe beam, and delayed probing of the Raman coherence enables elimination of interference from nonresonant four-wave mixing processes. Temperatures inferred from rotational spectra are sensitive to the probe delay because of the rotational-level dependence of collisional dephasing of Raman coherences. The sensitivity decreases, however, with increasing temperature, and accurate temperature measurements in a flame are demonstrated using a standard frequency-domain analysis of the spectra.
采用皮秒持续时间激光脉冲的时间分辨纯旋转相干反斯托克斯拉曼光谱学被用于气体测温。皮秒激光脉冲的使用显著减少了探测光束散射引起的背景，并且拉曼相干的延迟探测使得能够消除来自非共振四波混频过程的干扰。由于拉曼相干的碰撞退相对转动能级的依赖性，从转动光谱推断出的温度对探测延迟很敏感。然而，灵敏度随着温度的升高而降低，并且通过对光谱进行标准的频域分析，在火焰中成功地进行了精确的温度测量。
