Lanthanide ions doped upconversion luminescence materials have attracted great attention due to their potential applications in anti-counterfeiting, volumetric display, optical multiplexing, and bioimaging. Previous studies showed that it is possible to control transient states of lanthanide ions, enabling a large luminescence color gamut in one fixed composition upconversion material. However, the influences of material characteristics and excitation conditions on transient states have not been fully understood. Here we experimentally demonstrated that three factors, namely, doping concentration, excitation pulse width, and excitation pulse peak intensity, can be utilized to effectively control the transient states of NaYF₄:20%Yb/0.5%Er and NaYF₄:90%Yb/0.5%Er microrods for upconversion emission color adjustment and theoretically studied their temporal responses. Moreover, we demonstrated a proof of concept of a fluorescence anti-counterfeiting application based on the distinguishable transient-state properties of the upconversion microrods.

掺杂镧系离子的上转换发光材料由于其在防伪，体积显示，光学多路复用和生物成像中的潜在应用而备受关注。先前的研究表明，可以控制镧系元素离子的瞬态，从而在一种固定成分的上转换材料中实现较大的发光色域。但是，尚未充分了解材料特性和激发条件对瞬态的影响。在这里，我们通过实验证明了掺杂浓度，激发脉冲宽度和激发脉冲峰值强度这三个因素可以有效地控制NaYF ₄的瞬态：20％Yb / 0.5％Er和NaYF ₄：90％Yb / 0.5％Er微棒用于上转换发射颜色调整，并从理论上研究它们的时间响应。此外，我们展示了基于上转换微棒的独特瞬态特性的荧光防伪应用概念的证明。