【作者】 董国飞；

【导师】 曾繁明；

【作者基本信息】 长春理工大学 ， 材料物理与化学， 2011， 硕士

【摘要】 Tm,Ho:BaY2F8激光晶体是一种新型的近红外激光晶体材料,通过激发能够发射出2μmm的激光。2μm激光具有传输性能好,易被生物组织吸收,对人眼无害等优点,现在被广泛应用于军事,医疗,生物等各种领域。运用Tm,Ho:BaY2F8激光晶体的上转换特性,可以实现激光的上转换输出。本文介绍了Tm,Ho:BaY2F8激光晶体从多晶料到晶体的合成及生长。利用XRD,TG-DSC,荧光光谱及扫描电子显微分析等手段研究了多晶料及晶体的结构和性能。通过XRD分析得出,采用高温固相法在最佳温度960℃下合成的Tm,Ho:BaY2F8多晶料,晶粒尺寸范围为200—550nm,结晶度为76.88%；并发现运用双坩埚进行实验能够提高合成的多晶料的质量。采用提拉法生长出来了5%Tm,0.5%Ho:BaY2F8晶体,并对晶体进行了XRD、吸收和激发光谱分析。光谱分析结果表明：Tm,Ho:BaY2F8晶体在700到850nm范围内的吸收峰对应Tm3+离子的3H6→3H4能级跃迁；晶体在1400nm到2100nm范围内的吸收峰对应Tm3+离子的3H6→3F4能级跃迁和Ho3+离子的5I8→5I7能级跃迁；运用780nm激光激发晶体能够得到波长为2.056μm的近红外激光。运用水热法成功的生长出了Tm,Ho:BaY2F8纳米晶。通过XRD光谱分析得出了最佳的工艺参数；通过扫描电子显微分析对生长出的晶体进行了形貌结构分析；通过荧光光谱分析得出掺杂浓度为5%Tm3+和0.5%Ho3+的Tm,Ho:BaY2F8(？)内米晶的上转换效率最高。更多还原

【Abstract】 Tm,Ho:BaY2Fg laser crystal is a new type of near-infrared laser crystal materials, which is excited to be obtained 2um laser.2μm laser have a lot of advantages, such as good transmission performance, easyly be absorbed by biological tissue, Human eye harmless and so on. Now it has been widely used in the military, medicine, biology etc. The upconversion performance of Tm,Ho;BaY2F8 laser crystal can realize laser upconversion output.In the paper, it is introduced that the Tm,Ho:BaY2F8 polycrystalline material had be obtained and Tm,Ho:BaY2F8 laser crystal had be grown. XRD, TG-DSC, fluorescent spectroscopy and Field emission scanning electron microscopy have been used to study structure and spectral properties of polycrystalline material and crystal.The XRD results showed that Tm,Ho:BaY2Fg polycrystalline material was obtained at 960℃by the High-temperature solid-phase method. Crystal particle size was about 200nm-550nm, and the degree of crystallinity was 76.88%. that double crucible is used in experiment can improve polycrystalline material quality.5%Tm,0.5%Ho:BaY2F8 crystal is grown by Czochralski method, which is analysised by XRD, Absorption spectroscopy and Stimulate spectrum. The absorption bands between 700nm and 85Onm attributed to the Tm3+:3H6→3H4 level transition. The absorption bands between 1400nm and 2100nm attributed to the Tm3+:JH6→3F4 level transition and Ho3+:5I8→5I7 level transition.5%Tm，0.5%Ho:BaY2F8 crystal is stimulated by 780nm laser to get 2.056μm near infrared laser.Tm,Ho:BaY2F8nanoscale crystals is successfully grown by hydrothermal method. We had got the best process parameters by XRD concluded. Crystal morphology was analysised by Field emission scanning electron microscopy. According to the fluorescence spectrum analysis, the results showed that when the doping concentration 5%Tm3+and 0.5%Ho3+of Tm,Ho:BaY2F8 nanoscale crystals, the Up-conversion efficiency is the highest.更多还原