Pump-power-controlled luminescence switching in Yb3+∕Tm3+ codoped water-free low silica calcium aluminosilicate glasses

Abstract

Intense infrared-to-visible upconversion emissions in Tm3+∕Yb3+ codoped water-free low silica calcium aluminosilicate glasses have been obtained under excitation at 976nm. The results showed that as the pump power/intensity is increased, a reduction of up to one order of magnitude at the 800∕480nm emitted intensity ratio is observed; characterizing what can be denominated as luminescent switching. The physical origin of this switching is discussed and explained in terms of the tailoring of luminescent switchers to operate in a large range of pump powers, what could be used in the development of sensors and networks for optical processing and optical communications.

Upconversion luminescence and magnetic properties of ligand-free monodisperse lanthanide doped BaGdF5 nanocrystals

“…The research interests of lanthanide (Ln 3 þ )-doped upconversion (UC) nanocrystals (NCs) are increasing due to their particular optical properties [1] and these properties enable them to have potential applications in solid-state lasers [2], multi-color threedimensional displays [3], optical processing sensors [4] and solar cells [5]. In particular, UC NCs are envisioned to be the most appropriate candidates for fluorescent labels in biomedicine imaging due to the advantages such as the deep penetration depth of infrared excitation, excellent photo-stability and absence of auto-fluorescence in contrast to traditional fluorescent dyes, semiconductor quantum dots and down-conversion NCs [5][6][7][8][9].…”

Spectral tuning via multi-phonon-assisted stokes and anti-stokes excitations in LaF3: Tm3+ nanoparticles

“…4. It is worth mentioning that the temperature has a big effect on the ratio of NIR to blue luminescence, which is important for potential application in thermal sensors [52,53].…”

Upconversion emission from amorphous Y2O3:Tm3+, Yb3+ prepared by nanosecond pulsed laser irradiation

“…This indicates that three or two photons are required to populate the 1 G 4 and 3 H 4 level, respectively. Due to the mismatch of the energy level gap of Tm 3+ ion and the pump photon, the 1 G 4 level is populated by three step energy transfer while the 3 H 4 level is populated by two step energy transfer from the Yb 3+ ions to the Tm 3+ ion, as illustrated in the simplified energy level diagram in Figure 5 [7,20]. Briefly, the Yb 3+ ions are excited by 976 nm photons and transit from the ground state 2 F 7/2 to 2 F 5/2 .…”

“…In the recent years, upconversion (UC) emissions from rare earth doped materials have gained much attention due to many potential applications, such as all-solid state lasers [1,2], threedimensional displays [3], biological labeling [4][5][6], and luminescent switchers [7]. Excitation is easily achieved by a commercially available continuous wave (CW) infrared diode laser, which is compact, power-rich, and inexpensive.…”