NO分子共振增强的多光子离化机制  

Mechanism of Resonance Enhanced Multiphoton Ionization of NO Molecule

作　　者：张贵银[1] 张连水[1] 杨晓冬[1] 孙博[1] 

机构地区：[1]河北大学物理科学与技术学院

出　　处：《光谱学与光谱分析》2004年第11期1293-1295,共3页Spectroscopy and Spectral Analysis

基　　金：河北省自然科学基金(102090)资助项目

摘　　要：用皮秒NdYAG激光器泵浦光学参量发生放大器做激发源,获得了420～480nm波长范围内NO分子的多光子离化谱。通过对谱线的归属,分析确定了NO分子的离化为以Α2Σ为中间共振态的(2+2)共振增强的多光子离化过程。以速率方程为基础,利用激光脉宽较窄(35ps)的条件,推导出离化信号随激光强度呈近四次方变化关系,与实验测量结果相符,这可为用共振增强多光子离化(REMPI)光谱技术探测污染物NO分子提供实验参考。NO molecule is a diatomic molecule with different nucleus. It is a serious pollutant and is harmful to the health of the generation. It comes mainly from inflammation process using coal as burning material. So researchers have always been interested in it. The Resonance-Enhanced Multi-Photon Ionization (REMPI) spectrum of NO has been obtained in the range of 420-480 run with a Nd:YAG laser pumped optical parametric generator and amplifier as the radiation source. The ionization pathway of NO molecule was acquired with the assignment of the spectral lines. NO molecules are ionized via the resonant intermediate state A(2)-Sigma(+) and by a (2 + 2) REMPI process. On the basis of theoretical rate equation and with the condition that the duration of the laser pulse is very short (approximately 35ps), the dependence of ion signals on laser intensity was deduced. The variation of the ionization signal versus laser intensity is near quartic. This is in good agreement with the experimental result.

关 键 词：NO分子 光子 共振态 光学参量 变化关系 推导 波长范围 ND:YAG激光器 泵浦光 放大器 

分 类 号：O433[机械工程—光学工程] TN248[理学—光学]