STUDIES ON HYPERFINE STRUCTURE AND ISOTOPE SHIFT OF SOME EXCITED STATES IN Yb AND Tm ATOMS

The hyperfine structures and isotope shifts in some excited states of Yb and Tm have been measured using laser-atomic beam interaction, stepwise excitation and fluorescence detection techniques. From the experimental results, magnetic dipole hyperfine constants A and electric quadrupole hyperfine constants B have been derived. So for as we know, the A factor of [4f¹²5d6s6p]9/2 level in Tm is given for the first time.     

锌掺杂半导体材料的共振电离质谱分析

本文简要地描述了激光共振电离质谱的实验装置和测量方法,给出了用共振电离质谱方法对锌掺杂化合物半导体材料进行分析的光谱和质谱图,并估计了用这种方法进行痕量分析可能达到的检测限.     

光磁共振实验中双量子跃迁及射频场谐波干扰

由于射频场谐波的存在,致使其二次谐波的共振跃迁与双量子跃迁信号重叠。因此观察双量子跃迁,必须首先排除射频场二次谐波共振的影响,本文分析了光磁双共振实验中关于双量子跃迁产生的条件、判断和观测,并分析了多频率共振的原因。     

太赫兹波的产生、传播和探测

 太赫兹（THz）辐射通常指的是频率在0·1THz～10THz之间的电磁波,其波段在微波和红外之间,见图1。THz电磁辐射具有非常独特的性质,它可以透过各种生物体、电介质材料以及气相物质,这些介质在THz波段具有丰富的吸收和色散性质,通过测量并分析样品的THz信号便可以获得关于材料中的物质成分和物理、化学以及生物学信息。太赫兹频域在高数据率通信、保密通信、精确制导和隐藏武器探测等方面有重要的应用。因此,近年来这个新兴的研究领域---THz电磁辐射的产生及应用,正在受到各国科学家的极大关注。     

单原子检测及其应用

一、引言近年来,大功率可调谐激光器的出现使激光光谱分析痕量元素的技术取得了重大的突破,现在,已经达到了分析技术的极限灵敏度——单个原子。许多研究者都进行了这方面的研究工作。所谓单原子检测(One Atom Detection).就是:在被检测的灵敏体积中可以检测出单个     

Investigation of Chlorophyll Protein 43 and 47 Denaturation by Terahertz Time-Domain Spectroscopy

We demonstrate the applications of terahertz time-domain spectroscopy to distinguish conformation changes of the chlorophyll proteins CP43 and CP47 induced by the treatment of guanidine hydrochloride, light irradiation and heating. It is indicated that THz transmission spectroscopy can be used for monitoring protein denaturation and associated conformation change processes in a feasible and effective way.     

汽车排放污染物的共振增强多光子电离光谱分析

汽车排放的主要污染物为CO,HC,NOx(x=1,2）,SO2,Pb,苯丙芘,固体颗粒等[1],其尾气的检测对维护人类自身健康具有十分重要的意义．共振增强多光子电离光谱（Resonant Enhanced Multi-Photonionization,REMPI）是一种超灵敏光谱检测技术,它的灵敏度比LIF（Laser InducedFluorescence）还要高．1979年,Brophy和Rentttner[2]提出了REMPI可以作为检测大气污染的方法．后来,不同的研究小组采用了不同的REMPI方案对大气污染类分子进行了测量研究［3-6]．由于采用可调谐染料激光器为光源,可以使用同一种染料对几种具有相近特征波长的分子进行同时测定．本文报     

Energy levels of perturbed 6pnd J = 2 Rydberg states of Pb I by multichannel quantum defect theory

Energy levels of the odd-parity 6pnd J=2 Rydberg states of atomic lead are analyzed by the multichannel quantum defect theory (MQDT) with previous experimental energy levels. The 6pnd (6≤n ≤ 63) J=2 Rydberg energy levels are calculated and optimal MQDT parameters were obtained. Using these parameters, admixture coefficients for each level are calculated to designate the level denotations. The results show that strong channel mixings exist for the levels near the 6p6d (3/2)[5/2]2° and 6p6d (3/2)[3/2]2° pertubers. The five-channel model different from that in literature is used to predict 21 energy positions of 6pnd (1/2)[3/2]2° levels and to determine the denotations of all the 6pnd J=2 Rydberg states under 59788 cm-1 for Pb I.     

铥原子中等能量能级自然辐射寿命的时间分辨荧光测量

报道铥(Tm)原子10个中等能量激发能级自然辐射寿命的实验测量值.采用两台脉冲染料激光器将铥原子从基态激发到待测能级,再从铥原子激发态所释放的荧光随时间衰变的规律推算出自然辐射寿命值.测量精确度为10％.     

锌掺杂产导体材料的共振电离质谱分析

本文简要地描述了激光共振电离质谱的实验装置的测量方法,给出了用共振电离质谱方法对锌掺杂化合物半导体材料进行分析的光谱和质谱图,并估计了用这种方法进行奶量分析可能达到的检测限