Radioluminescence and thermoluminescence of rare earth element and phosphorus-doped zircon

Abstract

The radioluminescence and thermoluminescence spectra of synthetic zircon crystals doped with individual trivalent rare earth element (REE) ions (Pr, Sm, Eu, Gd, Dy, Ho Er, and Yb) and P are reported in the temperature range 25 to 673 K. Although there is some intrinsic UV/blue emission from the host lattice, the dominant signals are from the rare-earth sites, with signals characteristic of the REE 3+ states. The shapes of the glow curves are different for each dopant, and there are distinct differences between glow peak temperatures for different rare-earth lines of the same element. Within the overall set of signals there are indications of linear trends in which some glow peak temperatures vary as a function of the ionic size of the rare earth ions. The temperature shifts of the peaks are considerable, up to 200°, and much larger than those cited in other rare-earth-doped crystals of LaF 3 and Bi 4 Ge 3 O 12 . The data clearly suggest that the rare-earth ions are active both in the trapping and luminescence steps, and hence the TL occurs within localized defect complexes that include REE 3+ ions.

Ionoluminiscencia de silicatos de utilización en cerámica a temperaturas criogenicas

“…La desaparición del pico 340 nm a 40 K es exactamente contraria al caso de los tectosilicatos donde siempre se crea o aumenta bajando la temperatura. El espectro criogénico de IL perfila perfectamente las emisiones de Dy 3+ a 314 nm, 486 nm y 578 nm como activador mas frecuente en circones naturales (6)(7). Otras emisiones con mas difícil asignación de defecto asociado son las azules a 400 nm, porque coinciden con los centros [AlO 4 ]° de los tectosilicatos, así como el grupo UV 290 nm, 236 nm y 259 nm que aumenta por estrés termal y que parece relacionado con la propia red silicatada.…”

Annealing effects on cathodoluminescence of zircon

“…Such multiple narrow peaks in green and red-IR regions have been also confirmed in Dy 3+ -doped synthetic zircon Rémond et al, 1995). Additionally, Dy 3+ -activated emissions have been recognized not only in CL, but also in ionoluminescence (IL), thermoluminescence (TL), and photoluminescence (PL) (e.g., Karali et al, 2000;Finch et al, 2004;Gaft et al, 2005). Based on theoretical energy states in zircon, an emission peak at 480 nm is assigned to the transition of electron from 4 F 9/2 to 6 H 15/2 , the peak at 580 nm to the transition from 4 F 9/2 to 6 H 13/2 and the peak at 760 nm to the transition from 4 F 9/2 to 6 H 9/2 via 6 F 11/2 (Dieke and Crosswhite, 1963;Karali et al, 2000).…”

“…Based on theoretical energy states in zircon, an emission peak at 480 nm is assigned to the transition of electron from 4 F 9/2 to 6 H 15/2 , the peak at 580 nm to the transition from 4 F 9/2 to 6 H 13/2 and the peak at 760 nm to the transition from 4 F 9/2 to 6 H 9/2 via 6 F 11/2 (Dieke and Crosswhite, 1963;Karali et al, 2000). According to the previous CL, IL, TL, and PL studies, luminescent properties of weak emission peaks at 315, 405, 455, and 665 , and Dy 3+ impurity centers, respectively (Yang et al, 1992;Cesbron et al, 1995;Rémond et al, 1995;Karali et al, 2000;Nasdala et al, 2002;Hanchar and Hoskin, 2003;Finch et al, 2004;Gaft et al, 2005).…”

Gamma radiation effects on TL and EPR on natural zircon

“…All four TL peaks have supralinear behaviors. Karaly [3] produced zircon in laboratory doped with Pr, Sm, Eu, Gd, Dy, Ho, Er and Yb and found TL peaks in the range 25 to 675 K. Each rare earth has characteristic light emission. Turkin [4] attributed the 150 o C TL peak emission to Dy and Tb.…”