Abstract:Mid-infrared lasers are very suitable for high-sensitive trace-gases detection in that their wavelengths cover the fundamental absorption lines of most gases. Quantum-cascade lasers have been demonstrated to be ideal light sources with their especially high power, wide range of tuning capability and favorable operating condition on room-temperature. The intra-pulse spectroscopy based on a room-temperature distributed-feedback pulsed QC laser is a simple and effective trace gas detective method to detect trace-gas qualitatively or quantificationally. When a long excitation pulse is applied to a QC laser, the laser frequency tunes almost linearly to lower wave number (lower frequency) as a function of time so all absorption spectral elements are recorded during a single laser pulse. In the present paper, the method was introduced, and identification of N2O spectral fingerprint using this spectroscopy was demonstrated experimentally. The thermal chirp from a 500 ns long excitation pulse was applied to a quantum-cascade laser to get a fast wavelength scanning, thus a wave number tuning of about 1 cm-1 was produced. The N2O absorption spectrum centered at 1 273.7 cm-1 was also obtained. The measured absorption spectrum is consistent with HITRAN data precisely.
王 敏,张玉钧*,刘文清,阚瑞峰,陈臻懿,汤媛媛,刘建国. 基于室温量子级联激光器的脉内光谱技术测量N2O[J]. 光谱学与光谱分析, 2009, 29(12): 3181-3184.
WANG Min, ZHANG Yu-jun*, LIU Wen-qing, KAN Rui-feng, CHEN Zhen-yi, TANG Yuan-yuan, LIU Jian-guo . Intra-Pulse Spectroscopy Based on Room-Temperature Pulsed Quantum-Cascade Laser for N2O Detection. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2009, 29(12): 3181-3184.
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