当前位置: X-MOL 学术Anal. Chem. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Heterodyne Phase-Sensitive Dispersion Spectroscopy in the Mid-Infrared with a Quantum Cascade Laser
Analytical Chemistry ( IF 6.7 ) Pub Date : 2017-05-08 00:00:00 , DOI: 10.1021/acs.analchem.7b00303
Pedro Martín-Mateos 1 , Jakob Hayden 2 , Pablo Acedo 1 , Bernhard Lendl 2
Affiliation  

Molecular dispersion spectroscopy encompasses a group of spectroscopic techniques for gas analysis that retrieve the characteristics of the sample from the measurement of the profile of its refractive index in the vicinity of molecular resonances. This approach, which is in clear contrast to traditional methods based on the detection of absorption, provides inherent immunity to power fluctuations, calibration-free operation, and an output that is linearly dependent on gas concentration. Heterodyne phase-sensitive dispersion spectroscopy (HPSDS) is a very recently proposed technique for molecular dispersion spectroscopy based on tunable lasers that is characterized by a very simple architecture in which data processing and concentration retrieval are straightforward. Different HPSDS implementations have been experimentally validated in the near-IR. Here, we present the first demonstration of HPSDS in the mid-IR using a directly modulated quantum cascade laser for the measurement of CO. The setup is put under test to characterize its response to changing concentrations, pressures, and levels of optical intensity on the detector, and the limit of detection is estimated. Besides this, an experimental comparison with wavelength modulation spectroscopy with second-harmonic detection (2f-WMS) is performed and discussed in detail in order to offer a clear view of the benefits and drawbacks that HPSDS can provide over what we could consider the reference method for gas analysis based on tunable laser spectroscopy.

中文翻译:

量子级联激光器在中红外波段中的外差相敏感色散光谱

分子分散光谱学包括一组用于气体分析的光谱学技术,这些技术可通过测量分子共振附近的折射率分布来检索样品的特征。与基于吸收的检测的传统方法形成鲜明对比的是,该方法具有固有的抗功率波动,免校准操作以及线性依赖于气体浓度的输出的能力。外差相敏色散光谱法(HPSDS)是最近基于可调谐激光器提出的用于分子色散光谱法的技术,其特征是非常简单的体系结构,其中数据处理和浓度检索很简单。不同的HPSDS实施方案已在近红外实验中得到验证。在这里,我们展示了使用直接调制的量子级联激光器在中红外条件下对HPSDS进行的首次演示,该激光器用于测量CO。该装置正在测试中,以表征其对浓度,压力和光强水平变化的响应。检测器,并估计检测限。除此之外,还进行了与带有二次谐波检测(2f-WMS)的波长调制光谱的实验比较,并进行了详细讨论,以便清楚地了解HPSDS可以提供​​的优于我们认为的参考方法的优缺点。用于基于可调谐激光光谱的气体分析。对该装置进行测试,以表征其对检测器上浓度,压力和光强度水平变化的响应,并估算检测极限。除此之外,还进行了与带有二次谐波检测的波长调制光谱(2f-WMS)的实验比较,并进行了详细讨论,以便清楚地了解HPSDS所提供的利弊,而不是我们可以考虑的参考方法。用于基于可调谐激光光谱的气体分析。对该装置进行测试,以表征其对检测器上浓度,压力和光强度水平变化的响应,并估算检测极限。除此之外,还进行了与带有二次谐波检测的波长调制光谱(2f-WMS)的实验比较,并进行了详细讨论,以便清楚地了解HPSDS所提供的利弊,而不是我们可以考虑的参考方法。用于基于可调谐激光光谱的气体分析。
更新日期:2017-05-16
down
wechat
bug