Upconversion processes in Er3+-doped KPb2Cl5 -: art. no. 205203
Upconversion processes in Er3+-doped KPb2Cl5 -: art. no. 205203
复制标题
DOI：
10.1103/physrevb.69.205203
复制
发表时间：
2004-05-01
影响因子：
3.7
通讯作者：
Fernández, J
中科院分区：
文献类型：
--
作者：
Balda, R;Garcia-Adeva, AJ;Fernández, J
在这项工作中，我们报道了在I-4(9/2)激发下，掺Er3+的低声子能量基质材料KPb2Cl5的红外-可见光上转换发光。利用稳态和时间分辨激光光谱研究了上转换机制。当激发波长与I-4(9/2)能级(约800 nm)共振时，上转换发射来自H-2(9/2)能级和S-4(3/2)能级。这些上转换发射是通过能量转移上转换过程发生的。然而，在能量低于I-4(9/2)的非共振激发下，主要发射来自H-2能级(9/2)。后者的上转换发射可以归因于泵浦辐射的激发态吸收。脉冲红外激发后上转换发光的时间演化和上转换发光激发光谱支持了H-2(9/2)和S-4(3/2)两个能级不同的上转换发光机制。速率方程分析已经被用来识别和表征负责观察到的荧光行为的能量转移过程。
In this work we report infrared to visible upconversion luminescence in the low phonon-energy host material KPb2Cl5 doped with Er3+ ions under I-4(9/2) excitation. The upconversion mechanisms are investigated by using steady-state and time-resolved laser spectroscopy. When the excitation wavelength is resonant with the I-4(9/2) level (approximate to800 nm), the upconverted emission originates from the levels H-2(9/2) and S-4(3/2). These upconverted emissions occur via energy-transfer upconversion processes. However, under nonresonant excitation at lower energies than I-4(9/2), the main emission results from the level H-2(9/2). This latter upconverted emission can be attributed to excited-state absorption of the pump radiation. The proposed upconversion mechanisms responsible for the different emissions from the levels H-2(9/2) and S-4(3/2) are supported by both the time evolution of the upconversion luminescence after pulsed infrared excitation and the upconversion luminescence excitation spectra. Rate equation analysis has been used to identify and characterize the energy-transfer processes responsible for the observed fluorescence behavior.