Hg同位素对Hg的Zeeman效应相对强度的影响

比较了Hg的546.1 nm绿谱线Zeeman效应相对强度的理论计算和实验值,分析了Hg同位素位移及超精细结构对Hg的 Zeeman效应相对强度的影响.     

Properties of Hg implanted Hg1−x Cd x Te infrared detectors

Experimental performance parameters of Hg implanted Hg_1?x Cd _x Te photovoltaic detectors are analyzed. At 77K, for 8–14 μm band, a comparison is made between performances and theoretical ultimate diffusion limits in low frequency direct detection. Experimental features are well-explained by a model based on the Auger band-to-band process for carrier recombination. Peak detectivities exceeding 10¹¹ cm Hz^1/2W^?1, external quantum efficiencies as high as 90%, and zero-bias resistance-area products better than 1 Ω·cm² have been achieved in devices with 12 μm cutoff wavelengths. In the 3–5 μm band performances are far from the diffusion limit. Notwithstanding, at 77K zero-bias resistance-area products are better than 10⁴Ω·cm² and detectivities of the order of 10¹² cm Hz^1/2W^?1 were observed at 5 μm. Predominant generation-recombination contribution are present at room temperature in 1–1.3 μm photodiodes whose detectivities, primarily limited by the Johnson noise, at 1.3 μm are higher than 10¹¹ cm Hz^1/2W^?1 at 300 K. The high frequency response of the photodiodes is also discussed. Response times as low as 0.5 ns are reached despite some limitations arising from the implanted layer sheet resistance.     

新丰中子核素208Hg的发现

新丰中子同位素208Hg,首次从30MeV/u的12C束轰击厚的天然铅靶反应产物中被鉴定出来,208Hg的鉴别基于二步化学分离及γ活性分析,第一步,借助于在本工作中所发展起来的熔化靶装置和一种特殊的热色谱技术,实现了Hg元素产物高效、高选择性的分离,第二步则是周期性的提取随着收集样品中的丰中子Hg同位素的β—衰变而生长起来的Tl元素,在提取的Tl样品中,观察到能量为2614.6keV、半衰期为191±10~4 50s的γ活性,它只能被指定为208Hg的β—衰变子体208Tl,将测得的208Hg半衰期42±23 12min与理论预言进行了比较。 The new neutron-rich isotope 208Hg was identified for the first time from the reactionproducts in a thick natPb target bombarded by a 30MeV/u 12C beam. The identification of 208Hg wasbased on two-step chemical separation and γ activity analysis. The first step was the release,separation and collection of Hg element products with a high efficiency and good selectivity bymeans of a melt target device and a special thermochromatographic technique developed in presentwork. The second step was..     

Experimental evidence for the third level (А+) of Hg vacancy in Hg1−xCdxTe

Mercury vacancy in Hg_1-xCd_xTe is not a two-level (as it was supposed until now), but a three-level acceptor. A third, most shallow (1–1.5 meV) level (А⁺ state) appears due to a capture of a third hole by a neutral acceptor, after the two deeper vacancy levels (A^? and А⁰ states) are already occupied by holes. Due to a capture of nonequilibrium holes by neutral mercury vacancies (under radiation) a positive space charge region arises near an irradiated surface. This causes the anomalies of photoelectromagnetic effect, observed in р-Hg_1?xCd_xTe at T < 10–12 K.     

Optical properties of Hg1−xCdxTe

Optical properties of Hg_1−xCd_xTe are summarized in this study. Based on Penn-like models, the Moss relation and the Wemple and DiDomenico approach, calculations of energy gap, plasmon energy, Fermi energy, oscillator strength and electronic polarizability have been made. Comparisons are made with the data available in the literature. Details of the dependency of the properties on composition are presented.     

低温等离子体注入定向Hg氧化实验研究

燃煤烟气汞脱除的核心是单质汞(Hg~0)的高效氧化。本文基于低温等离子体技术,系统研究了放电电压、自由基源气体组成、烟气温度及烟气组分对氯自由基(Cl)注入强化氧化Hg~0的影响,结果发现降低注入点烟气温度、增加Cl注入量以及烟气中的NO均有利于Hg~0氧化,最佳放电电压的选取则与自由基源气体组成密切相关,一定条件下,注入极少量C_(12)(19 mg/m~3)即可获得97.9%的Hg~0氧化率。     

烟气中Hg的氧化机理的研究

本文对Ｈｇ与Ｃｌ２在烟气中的氧化反应进行了热力平衡计算和动力学计算。平衡计算的结果表明有ＣＩ元索存在时Ｈｇ的氧化率为１００％，而在相同的条件下动力学计算纺果为Ｈｇ的氧化率在２０％～８０％之间变化，与实验结果吻合。实际的氧化反应是一种超平衡状态，不能达到理想的平衡状态。因此应采用动力学与热力平衡分析相结合的方法研究Ｈｇ在烟气中的反应机理。同时，计算结果显示Ｃｌ含量对Ｈｇ的氧化率的影响很大．     

Hg原子光谱中的253.652nm互组合线

Ｈｇ原子光谱中的２５３．６５２ｎｍ互组合线翁斯灏（中国高科技中心，华东师范大学物理系，上海２０００６２）一、互组合跃迁１９１４年，德国物理学家Ｊ．Ｆｒａｎｃｋ和Ｇ．Ｈｅｒｔｚ利用电子与气体原子在非弹性碰撞中能量交换的分立特征，证明原子体系量子态的存在...     

Intrinsic carrier concentration in Hg1−xCdxTe

The effective mass of heavy holes has been determined on the basis of simultaneous analysis of the Hall coefficient and conductivity data obtained in the temperature region 100–300 K on well characterized p-type Hg_1–x Cd_xTe (x0·2) samples. Its value is 0·7m₀. The calculation of intrinsic carrier concentration for 0·19 x0·3 and 50 Kg T 300 K has been carried out using the above value of the effective mass of holes, Hansen's expression for the band gap and momentum matrix element from magneto-optical measurements.     

新核素209Hg的首次观察

报道了新重丰中子汞同位素２０９Ｈｇ的首次观察．The new neutron rich mercury isotope 209Hg has been identified from the separated mercury products producted in 600 MeV 18O+natPb (thick target) reaction. An on line, gas thermochromatographic technique and a special detection method were used. Four γ rays following the 209Hg decay were assigned. The half life of 209Hg was determined to be 35+9-6 s.      

Hg1—xCdxTe的共振拉曼散射

当入射光的光子能量接近Hg1-xCdxTe的Eo △o时,发现了Hg1-xCdxTe的共振拉曼散射,观察到了“禁戒”共振增强拉曼散射,同时也观察到了二级共振拉曼散射。分析了非共振条件下能在样品的（100）面观察到微弱的“禁戒”TO2模拟及在共振条件下“禁戒”TO2模大大增强的原因。通过分析,发现由双LO声子引起的二级共振拉曼散射主要由带内的Froehlich相互作用造成的。     

Hg2准分子远紫外发射谱带研究

报道在高压汞弧灯中首次观测到Ｈｇ２准分子在２２５－２３５ｎｍ谱区、峰值位于２３０ｎｍ左右的连续发射谱带。实验研究了此发射带随温度的变化，与理论计算的辐射谱相比较，两者十分相符。     

Hg对Bi系高温超导体织构生长的影响

用熔融织构工艺尝试制备的Ｂｉ系超导织构化样品并探索ＨｇＯ的加入对Ｂｉ系样品织构成形成的影响；结果发现，虽然样品（Ｂｉ，Ｐｂ）ＳｒＣａＣｕ的名义配比为２２２２３或２２３４，Ｘ射线衍射分析表明，所得织构样品均不为２２２３或２２３４相，而是２２１２相，原始样品的Ｈdisplay status     

Hg原子双光子激发截面的理论计算

以Hg原子为例,讨论了在Hartree-Slater自洽场近似的基础上,采用有限项近似和求解非齐次薛定谔方程相结合的方法,计算了双光子激发截面,该计算程序可以用于计算任意原子的双光子激发截面。 关键词：     

Photo-electronic phenomena in narrow gap Hg1−xCdxTe

The photo-electronic properties of Hg_1−xCd_xTe grown by molecular beam epitaxy (MBE) or by liquid phase epitaxy (LPE) were investigated using Fourier transform transmission spectroscopy, Fourier transform photoluminescence measurements, spectroscopic ellipsometry (SE), as well as magneto-optics and magnetic-field-dependent Hall studies. The investigation was carried out from liquid helium to room temperatures in the infrared band up to 10 μm. Some important impurities and defects states, including As, Sb, Ag, Fe impurities and Hg vacancy as well as their complexes in Hg_1−xCd_xTe, were carefully studied. We obtained the energy levels of the impurity states and their optical, electric and magnetic behaviors. By SE measurement, a number of very useful parameters, such as the real and the imaginary part of dielectric constant, gap energies corresponding to important critical points, were extracted. Mobility spectra and multi-carrier fitting procedure were used to separate the contributions to the measured mobility from the light holes, heavy holes, and electrons. As a result, the sign change of transverse conductivity component with applied magnetic-field is explained according to multi-carrier process.Hg_1−xCd_xTe (MCT) is one of the most important infrared materials, which is subjected to intensive studies. Its optical and electrical properties are widely used for the fabrication of high performance photoconductive and photovoltaic detectors. Some of characteristics that directly affect device performance, such as impurities, defects, as well as the lifetime of the minority carriers, remain as the major concern. Recently, the quality of the MCT material grown by MBE and LPE has been improved and accurate control over the doping levels for several dopants have been realized [1], [2], [3]. Following the progresses made in material preparation and doping, we are able to study the material systematically.In this paper, we report the recent progress made on the investigation of the electrical and optical properties of both doped and undoped MCT in our laboratory using Fourier transform spectroscopy (FTIR), photoluminescence, magneto-photoconductivity, transport measurement, as well as SE.     

Characterization of flash evaporated Hg1−xZnxTe films

Results of structural, optical and electrical properties of flash-evaporated Hg_1−xZn_xTe films. in the composition range 0.08 ⩽ x ⩽ 1, show that the films are formed by alloying HgTe and ZnTe. The optical band gap of these films increases from 0.04 to 2.26 eV with an increase in Zn concentration from 0.08 to 1.0. The band gap variation is not linear but shows a “bowing effect” familiar to pseudobinary solid solutions. An increase in resistivity with an increase in the substrate temperature can be related to larger grain size at the higher substrate temperatures in these p-type films. The films exhibit higher conductivity for the Hg-rich films which decreases linearly as the Zn concentration is increased.     

Hg和Pb超变形带的精确计算

利用从Bohr哈密顿量导出的转动谱abc公式E(I)=a[1+cL(I+1)][1+bI(I+1)－1],分析了已观测到的Hg和Pb同位素的超变形核转动带.计算结果与观测结果惊人地符合.几乎全部计算值与观测值的偏差│δ│≤0.5keV.对于这些超变形带中目前尚未测出的一些跃迁能量也进行了计算,可作为探测它们的有价值的参考.     

新重丰中子核素￣(209)Hg

报道了重丰中子核素２０９Ｈｇ的首次合成、鉴别和半衰期测定．