Synthesis and efficient near-infrared quantum cutting of Pr3+/Yb3+ co-doped LiYF4 single crystals

Abstract

Yttrium lithium fluoride single crystals doped with trivalent lanthanide ions Pr3+ and Yb3+ are prepared by an improved Bridgman method. X-ray diffraction, photoluminescence excitation, and emission spectra and decay curves are measured to investigate the structural and luminescent properties of the crystals. An efficient near-infrared quantum cutting downconversion from the crystals was observed. The downconversion involves the emission of two near-infrared photons for each blue photon absorbed at 480 nm via cross relaxation energy transfer from Pr3+ to Yb3+. Decay curve fitting using a modified Inokuti-Hirayama expression indicates dipole-dipole energy transfer from Pr3+ to Yb3+, which is consistent with the expected cross-relaxation scheme. The maximum quantum cutting efficiency approaches up to 168.4% in LiYF4: 0.28 mol. % Pr3+ and 6.02 mol. % Yb3+, and this is equivalent to 68.4% energy transfer efficiency.

Growth and spectral properties of Er3+/Tm3+ co‐doped LiYF4 single crystal

“…However, the decay lifetime decreases rapidly with the introduction of Tm 3+ ions. Energy transfer between Er 3+ and Tm 3+ ions appears, and the decay curves become non‐exponential with the average lifetimes decreasing rapidly from 13.14 ms to 4.56 ms. Because of the non‐exponential nature of the emission decay of these samples, we can evaluate the average experimental lifetime by the following equation where represents the luminescence intensity as a function of time t. The results are included in table .…”

Upconversion luminescence from terbium and ytterbium codoped LiYF 4 single crystals

“…In order to make sure enhancement of transparent inside the crystal cylinders, we use the higher Li-rich composition. The detailed process of the growth used for the improved Bridgman method has been reported in our previous works [13].…”

Luminescent properties of Eu3+-doped glass ceramics containing BaGdF5 nanocrystals under NUV-excitation for W-LEDs

“…Thus, the observed decay curves follow a single exponential function. The average fluorescent lifetimes of glass and glass ceramics specimens can be calculated by using the following formula [25]:…”