Up-conversion luminescence properties and temperature sensitivity of AgBi(MoO4)2: Yb3+/Er3+/Ho3+/Tm3+ phosphors

This work begins with a study of the synthesis of multi-color luminescence phosphors, and it is followed by a discussion of the temperature sensitivity of AgBi(MoO4)2:Yb3+/Er3+. Uniform and approximately spherical...

Ultraviolet C lasing at 263 nm from Ba2LaF7:Yb3+,Tm3+ upconversion nanocrystal microcavities

It is a daunting challenge to realize ultraviolet C (UVC) lasing (i.e., has a wavelength range from 200 to 275 nm) from upconversion nanocrystals due to their low upconversion efficiency. Here, we fabricate Ba₂LaF₇:Yb³⁺(90mol%), Tm³⁺(5mol%) upconversion nanocrystals from amorphous borosilicate glass to support emission at ∼263nm under 980 nm ns laser excitation. The excitation threshold can be further reduced from ∼130 to ∼26.5mJ/cm² by using a cylindrical microcavity. We also found that the growth of defect-free Ba₂LaF₇ nanocrystals with a high concentration of codoping Yb³⁺ and Tm³⁺ ions inside high optical damage threshold borosilicate glass is the key to achieving room-temperature UVC upconversion lasing under high-intensity excitation.

Hydrothermal synthesis of BaLu2F8:Ln3+ crystals: phase/morphology evolution, energy transfer and tunable multicolor luminescence

BaLu_2−xF₈:xLn³⁺ crystals have been synthesized via a one-step hydrothermal route without any surfactants.

One-step surfactant-free controllable synthesis and tunable up-conversion/down-shifting white light emissions of Sr2YF7 crystals doped with Ln3+ ions

In this work, uniform and monodisperse Sr₂YF₇ spheres were successfully synthesized via a facile one-step hydrothermal route without employing any surfactant.