CAJ | 학술논문

玻璃陶瓷又称为纳米微晶玻璃，是玻璃基质中包含约10 nm 的纳米微晶。在稀土掺杂的玻璃陶瓷中，稀土主要掺杂在氟化物纳米晶中。这种材料在发光应用中具有氟化物和氧化物的优点，是上转换发光和中红外发光效率高的基质材料。研究 Ho3＋/Yb3＋共掺杂的玻璃陶瓷（50SiO2-50PbF2-1．0YbF3-0.5HoF3）的上转换和中红外发光性质。玻璃陶瓷吸收光谱的半高宽比玻璃前驱物更窄，而且长波吸收峰的Stark劈裂更加明显，表明稀土离子掺杂在晶体中。通过吸收光谱计算了J-O 参数，Ω2值（0.17×10-20 cm2）比氟化物玻璃ZBLA（2．28×10-20 cm2）的低很多。在980 nm激光激发下，Ho3＋/Yb3＋共掺杂的玻璃陶瓷有很强的绿光上转换荧光和蓝光、红光上转换荧光。与玻璃相比，绿光和蓝光光强增强明显，而红光基本不变。玻璃陶瓷中的 Ho离子掺杂在声子能量低的PbF2晶体中，低的声子能量使发光能级的无辐射弛豫率降低，从而增加了绿光和蓝光的上转换效率。低的无辐射弛豫率同时也降低了红光上转换中间能级（5I7）的粒子数布居，因此红光上转换没有增强。在980 nm激光激发下 Ho3＋/Yb3＋共掺杂的玻璃陶瓷有很强的2.9μm 中红外荧光，而在玻璃前驱物中观察不到中红外荧光。
파리도자우칭위납미미정파리，시파리기질중포함약10 nm 적납미미정。재희토참잡적파리도자중，희토주요참잡재불화물납미정중。저충재료재발광응용중구유불화물화양화물적우점，시상전환발광화중홍외발광효솔고적기질재료。연구 Ho3＋/Yb3＋공참잡적파리도자（50SiO2-50PbF2-1．0YbF3-0.5HoF3）적상전환화중홍외발광성질。파리도자흡수광보적반고관비파리전구물경착，이차장파흡수봉적Stark벽렬경가명현，표명희토리자참잡재정체중。통과흡수광보계산료J-O 삼수，Ω2치（0.17×10-20 cm2）비불화물파리ZBLA（2．28×10-20 cm2）적저흔다。재980 nm격광격발하，Ho3＋/Yb3＋공참잡적파리도자유흔강적록광상전환형광화람광、홍광상전환형광。여파리상비，록광화람광광강증강명현，이홍광기본불변。파리도자중적 Ho리자참잡재성자능량저적PbF2정체중，저적성자능량사발광능급적무복사이예솔강저，종이증가료록광화람광적상전환효솔。저적무복사이예솔동시야강저료홍광상전환중간능급（5I7）적입자수포거，인차홍광상전환몰유증강。재980 nm격광격발하 Ho3＋/Yb3＋공참잡적파리도자유흔강적2.9μm 중홍외형광，이재파리전구물중관찰불도중홍외형광。
In the present paper,the upconversion and mid-infrared fluorescence properties of Ho3+/Yb3+ co-doped 50SiO2-50PbF2 glass ceramic (GC)were studied.The GC has the following composition (in mol%):50SiO2-50PbF2-1YbF3-0. 5HoF3 . The mixtures of about 10 g were placed in a corundum crucible and melted at 1 000 ℃ for 15 min in a SiC electric furnace in air and then poured on a brass plate.The GCs were obtained just by heat treatment at 450 ℃.The X-ray diffraction pattern of the GC indicates that very small size crystals were precipitated in the precursor glass by heat treatment.The GCs have as high trans-mittance as glasses.The GCs have higher absorption cross section and narrower absorption peaks compared to the corresponding glasses,indicating that fluoride is doped with Ho ions.The Judd-Ofelt intensity parameters were determined from the absorption spectrum and Judd-Ofelt theory.TheΩ2 value is 0. 17×10-20 cm2 lower than that of fluoride glass ZBLA (2. 28×10-20 cm2 ), because of Ho3+ doping in PbF2 microcrystal.The intense green upconversion light was observed in Ho3+/Yb3+ co-doped 50SiO2-50PbF2 GCs excited by 980 nm laser diode.A main emission band centered around 540 nm (green),and three week emission bands centered around 420 nm(violet),480 nm (blue),and 650 nm (red)which correspond to the Ho3+:(5F4→5I8), (5G6→5I8),(8K3→5I8)and (5F5→5I8)transitions,respectively,were simultaneously observed in GCs.Compared with the glass sample,GCs have significantly intension in the green and blue upconversion fluorescence,and not significant change in the red upconversion fluorescence.Those changes are because that Ho ion in GCs locates in lower phonon energy environment than in glasses.Lower phonon energy can make the nonradiative relaxation rate reduce,which improves the green light upconversion efficiency,at the same time reduces the population of the intermediate energy level (5 I7 )of the red light radiation.The 2.9μm mid-infrared light was observed in GC sample,but not in glass precursor excited by 980 nm laser diode.