College of Electronic and Optical Engineering & College of Microelectronics, Nanjing University of Posts and Telecommunications, Nanjing, 210023, People's Republic of China.
Phys Chem Chem Phys. 2018 Aug 29;20(34):22114-22122. doi: 10.1039/c8cp02974a.
Realization of the absorption and conversion of wide band infrared light have been a challenge in the field of upconversion luminescence. Herein, a facile physical approach is reported to realize the cooperative absorption and conversion of dual-band infrared light by NaGdF4:Er3+ nano-glass ceramics by employing a dual-mode excitation source (980 nm + 1545 nm). A synergistic effect of infrared photons induced by dual-wavelength infrared excitation is observed. The dual-mode excited red emission intensity is 2.76 times the total red emission intensities from 980 nm and 1545 nm single excitation. This upconversion synergistic effect can be modulated by adjusting the single excitation power, and it is proved to originate from ground and excited state absorption, in which the Er3+ ions in metastable states excited by 980 nm (or 1545 nm) photons are excited again by the 1545 nm (or 980 nm) infrared photons. A rate equation model is established to simulate the dynamic process in the dual-mode infrared upconversion process. The synergistic effect provides us with a way to convert two low-energy infrared photons into middle-energy visible photons to enhance the upconversion efficiency of rare earth ion doped glass ceramics.
在上转换发光领域，实现宽带红外光的吸收和转换一直是一个挑战。在此，通过采用双模式激发源（980nm+1545nm），报道了一种通过 NaGdF4:Er3+纳米玻璃陶瓷实现双频红外光协同吸收和转换的简便物理方法。观察到双波长红外激发诱导的红外光子协同效应。双模式激发的红色发射强度是 980nm 和 1545nm 单激发的总红色发射强度的 2.76 倍。这种上转换协同效应可以通过调整单激发功率来调节，并证明其源于基态和激发态吸收，其中处于亚稳态的 Er3+离子通过 980nm（或 1545nm）光子被激发，然后被 1545nm（或 980nm）红外光子再次激发。建立了速率方程模型来模拟双模式红外上转换过程中的动态过程。协同效应为我们提供了一种将两个低能量红外光子转换为中等能量可见光光子的方法，以提高稀土离子掺杂玻璃陶瓷的上转换效率。
