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This report focuses on research into waveguides prepared by K+-Na+ ion exchange with the help of an electric field, and the subsequent comparison with waveguides prepared by pure thermal ion
exchange. The goals of this work were to determine the characteristics of and to address the technological problems associated
with waveguides prepared in two types of highly pure optical glass: special soda-lime silica GIL49 glass produced from pure
raw materials and commercially prepared borosilicate BK7 glass. An appropriate chemical mixture, KNO3:Ca(NO3)2 in the molar ratio of 41:59, was used as the source of potassium ions. Experiments were conducted at temperatures between
250 and 410°C, and electric field values between 0 and 150 V/mm. The number of modes, depth, profile, and the change in refractive
index (Δn) were measured for samples from each type of glass under various technological conditions. All of these parameters
can be controlled accurately and repeatedly by the electric field. These experiments have also shown that a particular advantage
of these types of pure glass is the low waveguide optical losses (0.1 to 0.2 dB/cm) attainable. 相似文献
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为了研究YAG激光CO2激光行鼓膜造孔对听力的影响,我们用不同功率密度的激光照射豚鼠鼓膜不同时间后观察中耳和耳蜗显微和超微结构的变化。结果发现光关节末端输出功率1.58W/mm^2的CO2激光照射豚鼠鼓膜2秒,相同功率密度的YAG激光照射10秒可引起鼓膜穿孔,听骨链和耳蜗凝固或点状炭化;显微镜观察见凝固和炭化处柯蒂氏器官均明显破坏或变形,其内部分有炭化灶和/或炭化颗粒。激光输出功率密度愈大,损伤听 相似文献
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为了改善Cr4+:YAG被动调Q激光器的输出稳定性,采用了定向棱镜谐振腔,通过实验得到了以下结果:单脉冲能量稳定度由7.3%提高到2.2%,脉宽稳定度由13.5%提高到6.5%,频率精度由0.01%提高到0.005%,输出脉冲波形稳定光滑。研究表明,采用定向棱镜谐振腔技术的Cr4+:YAG被动调Q激光器的输出稳定性较原平平腔激光器得到了显著改善。另外还报道了定向棱镜谐振腔技术消除Cr4+:YAG被动调Q激光器子脉冲的现象。 相似文献
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利用四氯化硅(SiCl4)水解掺杂法结合高 频等离子体粉末熔融技术制备了Yb3+/Al3+共掺石英玻璃,并利用 X射 线衍射(XRD)、傅里叶变换红外(FTIR)光谱分析和热膨胀分析等对所制备玻璃样品的结 构特性、物理特性和光谱特 性进行了表征。结果表明,制备的Yb3+/Al3+共掺石英玻璃的密度和折 射率值与纯石英玻璃相接近,并且呈现出 较好的玻璃态,其热膨胀系数为2.87×10-6,具有较好的Yb3+和Al 3+掺杂均匀性,以及Yb3+典型的吸 收特性和发射特性,表明采用本文方法制备的Yb3+/Al3+共掺石英玻璃 已具备成为大功率激光材料的潜质。 相似文献
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通过溶液燃烧法以La(NO3)3·6H2O,Dy(NO3)3·9H2O和Al(NO3)3·9H2O及C2H5NO2为原材料制备纳米粉体Lal-xDyxA1O3(x=0,0.01,0.02,0.03,0.04,0.05).采用X射线衍射、扫描电子显微镜、紫外-可见漫反射光谱和荧光光谱研究晶体结构、形貌、发光强度等内容,结果表明,通过溶液燃烧法在800℃下煅烧4h,Dy3+离子进入到LaAlO3晶格中,荧光光谱分析结果表明Lal-xDyxAlO3粉体在370 nm的激发波长下,发光主峰位于423 nm处,在掺杂比例为0.03时发光强度最高,其禁带宽度5.54 eV与理论值5.6 eV相近. 相似文献
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以无水乙醇作反应溶液,采用室温共沉淀,合成 了CaHPO4:Tb3+绿色荧光粉。用X射线衍射(XRD)、 扫描电镜(SEM)、荧光(PL)光谱、热重(TG)和差示扫描量热(DSC)等分别对所得样品的相结构、形貌、发光 性能以及热稳定性进行研究。研究结果表明,在室温条件下,得到了纯三斜相CaHPO4:Tb 3+;当烧结温度为 400℃时,开始出现相结构转变;温度升高到500℃以上时,晶相完全转变为纯四方晶系Ca2P2O7,但样 品的形貌变化很小,都为分散性比较好、尺寸分布比较均匀的纳米颗粒。同时,利用激发光 谱和发射光谱 研究了Tb3+在CaHPO4和Ca2P2O7基质中的发光性能,在波长为370nm紫外光的激发下,都观察到Tb3+的特 征跃迁(5D4→7FJ,J=3~6),其中以5D4→7F5 跃迁发射(544nm)为主,而且CaHPO4:Tb3+的发光强度要明 显强于Ca2P2O7:Tb3+。 相似文献
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采用熔融法制备了锌铝锑磷酸盐(ZASP)玻璃荧光 体,研究了其荧光色彩对激发波长的依赖性和Dy3+掺杂的色彩调谐作用。短波紫外(U VC)和中波紫外(UVB)激发下,ZASP基质玻璃 呈现Sb3+的宽谱带发射,色彩位于蓝白光和蓝光区域。差异性光谱行为表明,玻璃中 存在异质 性的Sb3+发光中心,导致玻璃荧光对激发波长产生依赖行为。Dy3+引入ZASP玻 璃后,产生归属 于Dy3+的约484nm波长窄带发 射,其在UVC和UVB激发下的发光有效性相当程度上归因于Sb 3+到Dy3+的能量传递。Dy3+的暖色成分使ZASP玻璃荧光总体上从蓝白区 向白光区移动,同时 也对荧光的激发波长依赖趋势产生显著影响,丰富了荧光发射色彩的多样性,为高质量荧光 器件的研发提供了可能。 相似文献
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Ajay K. Srivastava Ashutosh Bhardwaj Kirti Ranjan Namrata Sudeep Chatterji R. K. Shivpuri 《Materials Science in Semiconductor Processing》2003,6(5-6):555-559
The influence of crystal damage on the electrical properties and the doping profile of the implanted p+–n junction has been studied at different annealing temperatures using process simulator TMA-SUPREM4. This was done by carrying out two different implantations; one with implantation dose of 1015 BF2+ ions/cm2 at an energy of 80 keV and other with 1015 B+ ions/cm2 at 17.93 keV. Substrate orientation 1 1 1 of phosphorus-doped n-type Si wafers of resistivity 4 kΩ cm and tilt 7° was used, and isochronally annealing was performed in N2 ambient for 180 min in temperature range between 400°C and 1350°C. The diode properties were analysed in terms of junction depth, sheet resistance. It has been found that for low thermal budget annealing, boron diffusion depth is insensitive to the variation in annealing temperature for BF2+-implanted devices, whereas, boron diffusion depth increases continuously for B+-implanted devices. In BF2+-implanted devices, fluorine diffusion improves the breakdown voltage of the silicon microstrip detector for annealing temperature upto 900°C.For high thermal budget annealing, it has been shown that the electrical characteristics of BF2+-implanted devices is similar to that obtained in B+-implanted devices. 相似文献