Dynamics of the Green and Red Upconversion Emissions in Yb³⁺‐Er³⁺‐Codoped Y₂O₃ Nanorods

Abstract

Efficient green and red upconversion emission inY2O3:Yb3+,Er3+nanorods under 978 nm radiation excitation is achieved. Experimental effective lifetimes, luminescent emissions, and nanorod sizes depend strongly on the solvent ratios used during the synthesis. A microscopic nonradiative energy transfer model is used to approach the dynamics of the green, red, and infrared emissions. The excellent agreement between simulated and experimental decay suggests that the energy transfer mechanisms responsible of the visible emission depend on the solvent ratio.

Visible upconversion emission and non-radiative direct Yb3+ to Er3+ energy transfer processes in nanocrystalline ZrO2:Yb3+,Er3+

“…In Ref. [27] the energy transfer rate Yb 3+ ( 2 F 5/2 , 2 F 7/2 )-Er 3+ ( 4 I 13/2 , 4 F 9/2 ) was estimated for Y 2 O 3 :Yb 3+ ,Er 3+ , and is 21 times smaller than the values found here for the system ZrO 2 :Yb 3+ ,Er 3+ . These results suggest that the direct Yb 3+ to Er 3+ energy transfer processes in ZrO 2 :Yb 3+ ,Er 3+ are extremely efficient and therefore ZrO 2 can be considered to be one of the best candidates for Er 3+ upconversion emission applications.…”

Upconversion microparticles as time-resolved luminescent probes for multiphoton microscopy: desired signal extraction from the streaking effect

“…1. 20 The efficiency of upconversion is determined by the lifetime of rare-earth ions metastable states, the probability of the exchange interaction, and the electron-phonon interaction. These parameters, in turn, are determined by the distance between ions, the symmetry of the nearest environment, and the presence of quenching impurities.…”