1.84 μ m emission of Tm3+ sensitized by Yb3+ ions in monoclinic KGd(WO4)2 single crystals

Abstract

By exciting at 940 nm, we have characterized the 1.84 m near infrared emission of trivalent thulium ions in Yb 3+ , Tm 3+ :KGd͑WO 4 ͒ 2 single crystals as a function of the dopant concentration and temperature, from 10 K to room temperature. An overall 3 H 6 Stark splitting of ϳ470 cm −1 for the Tm 3+ ions in the Yb 3+ , Tm 3+ :KGd͑WO 4 ͒ 2 was obtained. We also studied the blue emission at 476 nm ͑Tm 3+ ͒ and the near infrared emissions at 1.48 m ͑Tm 3+ ͒ and 1 m ͑Yb 3+ ͒ as a function of the dopant concentration. Experimental decay times of the 1 G 4 , 3 H 4 , and 3 F 4 ͑Tm 3+ ͒ and 2 F 5/2 ͑Yb 3+ ͒ excited states have been measured as a function of Yb 3+ and Tm 3+ ion concentrations. For the 3 F 4 → 3 H 6 transition of Tm 3+ ions, we used the reciprocity method to calculate the maximum emission cross section of 3.07ϫ 10 −20 cm 2 at 1.84 m for the polarization parallel to the N m principal optical direction.

Balancing power density based quantum yield characterization of upconverting nanoparticles for arbitrary excitation intensities

“…38,39 The strong emission peak centered at 1035 nm in Fig. 3b originates from the transition of Yb 3+ : 2 F 5/2 / 2 F 7/2 , [40][41][42] while the emissions in Fig. 3a at 450 nm, 474 nm and 646 nm are generated by the transitions of Tm 3+ : 1 D 2 / 3 F 4 , 1 G 4 / 3 H 6 and 1 G 4 / 3 F 4 , respectively.…”

Synthesis and photoluminescence characterization of Ce3 + and Dy3 + activated ALa(WO4)2(A = Na and Li) novel phosphors

“…Moreover, the luminescent properties of all the potential activators such as Ce 3+ and Dy 3+ activated ions have not been adequately studied. Only a few ions like Nd 3+ , Sm 3+ , Tm 3+ , Yb 3+ (Güell et al 2007), Ho 3+ (Kasprowicz et al 2007), Er 3+ (Mateos et al 2002) etc are reported as good activators in tungstate hosts for laser applications. This is probably because of the fact that Ce 3+ and Dy 3+ ions doped systems are not promising laser materials as other rare earth based systems.…”