PMN-32PT∶Er/Yb晶体的结构及性能研究

Investigation of Structure and Properties of PMN-32PT∶Er/Yb Crystals

为改善PMN-32PT晶体的光学性能,引入Er^(3+)和Yb^(3+)进行改性,采用高温溶液法生长了PMN-32PT∶Er/Yb弛豫铁电晶体.通过X射线衍射分析了晶体的相结构,利用高温介电温谱仪、准静态d33测试仪、紫外-可见-近红外吸收光谱仪及FLS980稳态瞬态荧光光谱仪分别测试了晶体的介电、压电、光吸收及上转换发光性能.研究结果表明:晶体具有纯的钙钛矿结构,居里温度(Tc)约为148.3℃,室温下最大压电常数为1 230pC/N,在紫外-可见-近红外波段晶体具有一定的光吸收特性.用波长为980nm的激光激发晶体,观察到强的绿光和红光发射带,分别对应于Er^(3+)的~4S_(3/2)→~4I_(15/2)和~4F_(9/2)→~4I_(15/2)的跃迁发射.晶体的~4S_(3/2)和~4F_(9/2)能级的平均寿命为91.40μs和167.28μs.稀土离子的掺入,使晶体具备了较强的光吸收和上转换发光特性.

PMN-32PT crystals co-doped with ions Er3+ and Yb3+ were grown by the flux method to improve its optical properties.The structure of as-grown crystals was performed by X-ray diffraction. The dielectric,piezoelectric constant,light absorption and UC emission properties were characterized by Agilent E4980A,Quasi-Static d33 tester,UV-VIS-NIR spectrophotometer and FLS980 steady-transient state spectrometer respectively.It was indicated:The crystals were of pure perovskite phase structure. The Curie temperature (Tc)was 148.3 ℃.The piezoelectric constant (d33 )of crystal was up to 1230 pC/N at room temperature.Special absorption at UV-VIS-NIR bands was obtained.Moreover,strong green and red emission were observed under the excitation at 980 nm,which corresponds to the transition emission of Er3+ from 2 H11/24 I15/2 ,4 S3/2→ 4 I15/2 (green),and 4 F9/2→ 4 I15/2 (red).In addition,mean energy level lifetime of 4S3/2 and 4F9/2 levels were 91.40 μs and 167.28 μs,respectively.The crystals posses strong light absorption and upconversion luminescence with rare earth doping.