【作者】 王庆艳；

【导师】 张中华；

【作者基本信息】 哈尔滨工业大学 ， 物理电子学， 2010， 博士

【摘要】 本文以工程应用为背景,系统地分析了影响铷光谱灯工作特性的因素,并对其进行了试验研究。应用不同能量质子和电子作为辐照源,研究了用于铷光谱灯壳材料的国产GG17玻璃的辐照效应,揭示了辐照缺陷产生的微观机理;对射频放电和不同加热条件的铷光谱灯泡玻壳进行了分析,确定了铷与玻壳发生化学反应的产物,建立了化学反应模型;在不同的灯基座温度和射频放电条件下,对铷光谱灯进行了光谱发光模式的研究,建立了铷光谱灯的环模式参数区间。研究结果表明,电子辐照、质子辐照及电子质子综合辐照都会对GG17玻璃的光学性能产生不同程度的影响。电子和高能质子辐照引起GG17玻璃的光学性能退化明显,尤其1MeV电子在辐照注量为1016/cm2时能引起铷D线波长（780.0nm和794.6nm）处的谱透过率下降幅度超过18%。相比较而言,低能质子辐照对铷D线的影响较弱。光学性能的退化主要来源于辐照诱导大量色心的出现。通过傅里叶红外变换光谱和电子顺磁共振谱等手段分析表明,辐照缺陷的主要类型为氧空穴心。电子和高能质子辐照产生的缺陷类型以硼氧空穴心为主,主要呈现电离效应;低能质子辐照产生的缺陷类型主要为硅氧空穴心和硼氧空穴心,主要呈现位移效应。针对不同辐照条件,建立了氧空穴心的产生机理。电子和高能质子辐照产生的硼氧空穴心是空穴被捕获在桥氧上;低能质子辐照产生的硼氧空穴心是空穴被捕获在非桥氧上。铷光谱灯作为抽运光源时,需要在一定的温度和射频电压条件下工作。长时间的加热和射频放电使得铷与玻壳发生相互作用—扩散和化学反应,从而导致金属铷消耗。当温度升高或射频激励电压增大时,铷在玻壳内的扩散能力及铷与玻壳的化学反应程度均增强。通过二次离子质谱、X射线光电子谱和扫描电镜/背散射衍射/能谱分析,确定了不同工作条件下铷在玻壳厚度方向上的分布。阐明了250℃加热和射频放电条件下铷灯中金属铷的消耗机理。利用X射线衍射和X射线光电子谱分析,给出了铷与玻壳发生相互作用的主要产物为铷的氧化物（Rb₂O,Rb₂O₂和RbO₂）、铷的硅酸盐（Rb₂Si₄O₉和Rb₂SiO₃）,以及铷的硼酸盐（RbBO₂）。影响铷光谱灯工作特性的另一重要因素为发光模式,主要受温度和射频激励电压的影响。当温度过高或射频激励电压过大时,将导致铷光谱灯发光模式由环模式向红模式发生转变,光强信号的信噪比下降并使铷光谱灯失效。铷光谱灯的温度愈高,发生模式转变所对应的最大射频激励电压愈小,由此确立了铷光谱灯环模式工作所对应的温度和射频电压参数。为了减弱铷与玻壳的相互作用和保证发光的稳定性,应在环模式发光的条件下以尽可能低的温度和射频电压工作,从而减缓铷光谱灯性能退化速率。深入研究玻壳材料在空间辐照环境作用下的损伤效应与机理,以及铷与玻壳相互作用机制,具有十分重要的工程应用背景及理论研究意义。更多还原

【Abstract】 Factors of affecting the rubidium spectral lamp performance were analysed systematically, and the corresponding experiments were performed under the background of engineering application. Radiation effects caused by protons and electrons with various energies were investigated for the GG17 borosilicate glass as envelope materials of rubidium spectral lamps. The mechanisms of radiation-induced defects were investigated. The glass envelope of rubidium spectral lamps under the conditions of RF discharge and various temperatures was analysed, and the chemical reaction between rubidium and glass envelope was characterized. The spectral performance of rubidium spectral lamps was investigated and the parameter range of ring mode was identified.Experimental results show that the electron irradiation, proton irradiation and simultaneous irradiation of electrons and protons affect the optical property of GG17 glasses to some different extent. The optical degradation of GG17 glass irradiated by electrons and higher energy protons is evident, especially 1MeV electrons with the fluence of 1016/cm2 could induce a spectral transmittance decrease over 18% at the rubidium D lines （780nm and 794.6nm）. In comparison, lower energy protons have a weak effect on the rubidium D line. The optical change results from a number of radiation-induced color centers. The results show that the main type of radiation defects is the oxygen hole center, determined by Electron Paramagnetic Resonance and Fourier Transform Infrared Spectroscopy. Electrons and higher energy protons mainly induce ionizing effect and the major defects are boron-oxygen hole centers. Lower energy protons mainly induce displacement effect and the primary defects are silicon-oxygen hole centers and boron-oxygen hole centers. The formation model of oxygen hole centers was presented for various irradiation conditions. The boron-oxygen hole centers induced by electrons and higher energy protons are due to holes trapped on bridging oxygens, while for lower energy protons as a result of holes trapped on non-bridging oxygens.Rubidium lamp serves as an optically pumped sources under a certain temperature and RF voltage. Heating and RF discharge for a long time could cause an interaction of the rubidium and glass envelope, including the rubidium diffusion into the glass envelope and the chemical reaction of rubidium and glass envelope, leading to rubidium loss. Both the diffusion and chemical reaction strongly depend on temperature and RF voltage. Rates of chemical reaction and rubidium diffusion are enhanced with increasing temperature and RF voltage. The rubidium diffusion process is examined by secondary ion mass spectra, X-ray photoelectron spectra and back-scattered diffraction analysis, giving rubidium profile distribution along glass wall for various work conditions. The main products of chemical reactions are rubidium-oxides （Rb₂O, Rb₂O₂ and RbO₂）, rubidium-silicates （Rb₂Si₄O₉ and Rb₂SiO₃） and rubidium-borates （RbBO₂）.Another important factor affecting rubidium lamp performance is luminescent mode, which is mainly cotrolled by temperatue and RF voltage. Change of the luminescent mode from a ring mode to a red mode arises as the temperature or RF voltage becomes too large, leading to a decrease in the signal-to-noise ratio of optical intensity and failure of the rubidium spectral lamp. The maximal RF voltage corresponding to the mode change decreases with increasing temperature, and the parameter range of temperature and RF voltage corresponding to the ring mode is identified.The rubidium lamp should work at the temperatures and RF voltages as low as possible under the ring mode in order to weaken the interaction of rubidium and glass and to guarantee the discharge stability. It could reduce the rate of performance degradation for rubidium lamps. It is important and significant for engineering application and theoretical research to reveal damage effects and mechanisms for the glass envelope material exposed by radaition environment, as well as the mechanism of the interaction between rubidium and glass envelope.更多还原