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+:2F5/2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.

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+:2F5/2→2F7/2 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.