YAG中Cr3+和Yb3+的发光特征以及Cr3+和Yb3+之间的能量传递过程

室温下观察了YAG:Cr³⁺,Yb³⁺材料在近红外区域的发光特性, 并通过对Cr³⁺:⁴T₂和Yb³⁺:²F_5/2能级辐射跃迁寿命以及它们布居时间的比较研究,提出了从Cr³⁺到Yb³⁺的能量传递机制,同时借助于能级图描述了从Cr³⁺到Yb³⁺的能量传递以及Cr³⁺和Yb³⁺的近红外发光过程。

Properties of NIR Emissions with Energy-transfer Processes in Cr3+-and Yb3+-doped Y3 Al5 O12 Powder Materials

Cr³⁺- and Yb³⁺-doped YAG powder samples were prepared and the energy transfer (ET) mechanism in the samples was evaluated by the photoluminescence (PL), photoluminescence excitation (PLE) and light-emitting lifetime. By taking advantage of the spin allowed ⁴A₂ → ⁴T₂ and ⁴A₂→⁴T₁ absorption of Cr³⁺ and the efficient energy transfer from Cr³⁺ to Yb³⁺, the broadband spectral conversion makes Yb³⁺:²F_5/2→²F_7/2 transition give off a desirable emission around 1 000 nm, which is according to the maximum spectral response of c-Si solar cells, and hence would lead to the enhancement of silicon solar photovoltaic conversion efficiency.