CAJ | 학술논문

中红外激光光源覆盖了大鼍气体的基频吸收带,尤其适合于痕量气体的高灵敏检测.其中具有高输出功率、宽调谐范围、能够在室温工作的量子级联激光器为高灵敏痕量气体检测技术的研究提供了理想的光源.基于脉冲量子级联激光器的脉内光谱技术提供了一种简单而又有效的测量痕量气体的方法.当一个长激发脉冲作用在激光器上时,激光器的频率随着脉冲持续时间的增加而线性减小,从而在单个脉冲上扫描出被测气体分子的特征吸收谱线,实现对目标气体的定性或者定量分析.介绍了基于分布式量子级联激光器的脉内光谱技术,并采用该技术对N_2O进行了光谱测量.一个500 ns的长激发脉冲应用在脉冲量子级联激光器上用于快速波长扫描,达到接近1 cm~(-1)的线性调谐范围,得到了中心在1 274 cm~(-1)附近的N_2O的吸收谱线,与HITRAN数据库相应的N_2O吸收谱线有着良好的一致性.
중홍외격광광원복개료대타기체적기빈흡수대,우기괄합우흔량기체적고령민검측.기중구유고수출공솔、관조해범위、능구재실온공작적양자급련격광기위고령민흔량기체검측기술적연구제공료이상적광원.기우맥충양자급련격광기적맥내광보기술제공료일충간단이우유효적측량흔량기체적방법.당일개장격발맥충작용재격광기상시,격광기적빈솔수착맥충지속시간적증가이선성감소,종이재단개맥충상소묘출피측기체분자적특정흡수보선,실현대목표기체적정성혹자정량분석.개소료기우분포식양자급련격광기적맥내광보기술,병채용해기술대N_2O진행료광보측량.일개500 ns적장격발맥충응용재맥충양자급련격광기상용우쾌속파장소묘,체도접근1 cm~(-1)적선성조해범위,득도료중심재1 274 cm~(-1)부근적N_2O적흡수보선,여HITRAN수거고상응적N_2O흡수보선유착량호적일치성.
Mid-infrared lasers are very suitable for high-sensitive trace-gases detection in that their wavelengths cover the funda-mental absorption lines of most gases. Quantum-cascade lasers have been demonstrated to be ideal light sources with their espe-cially high power, wide range of tuning capability and favorable operating condition on room-temperature. The intra-pulse spec-troscopy 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 recor-ded during a single laser pulse. In the present paper, the method was introduced, and identification of N_2O 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 N_2O absorption spectrum centered at 1 273.7 cm~(-1) was also obtained. The measured absorption spectrum is consistent with HITRAN data precisely.