Meert Katrien W, Morozov Vladimir A, Abakumov Artem M, Hadermann Joke, Poelman Dirk, Smet Philippe F
Opt Express. 2014 May 5;22 Suppl 3:A961-72. doi: 10.1364/OE.22.00A961.
In this paper the luminescence of the scheelite-based CaGd₂(₁-x)Eu₂x(WO₄)₄ solid solutions is investigated as a function of the Eu content and temperature. All phosphors show intense red luminescence due to the ⁵D₀ - ⁷F₂ transition in Eu³⁺, along with other transitions from the ⁵D₁ and ⁵D₀ excited states. For high Eu³⁺ concentrations the intensity ratio of the emission originating from the ⁵D₁ and ⁵D₀ levels has a non-conventional temperature dependence, which could be explained by a phonon-assisted cross-relaxation process. It is demonstrated that this intensity ratio can be used as a measure of temperature with high spatial resolution, allowing the use of these scheelites as thermographic phosphor. The main disadvantage of many thermographic phosphors, a decreasing signal for increasing temperature, is absent.
本文研究了基于白钨矿的CaGd₂(₁-x)Eu₂x(WO₄)₄固溶体的发光随Eu含量和温度的变化关系。所有磷光体由于Eu³⁺中的⁵D₀ - ⁷F₂跃迁以及来自⁵D₁和⁵D₀激发态的其他跃迁而呈现出强烈的红色发光。对于高Eu³⁺浓度，源自⁵D₁和⁵D₀能级的发射强度比具有非常规的温度依赖性，这可以通过声子辅助交叉弛豫过程来解释。结果表明，该强度比可作为具有高空间分辨率的温度测量指标，使得这些白钨矿可用作热成像磷光体。许多热成像磷光体的主要缺点，即温度升高信号减弱，在这些材料中不存在。
