Thermally induced ionization of 5d1 state of Ce3+ ion in Gd3Ga3Al2O12 host

Wu, Yuntao; Nikl, M.; Jarý, V.; Ren, Guohao

doi:10.1016/j.cplett.2013.04.068

Cited by 36 publications

(9 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…17 Unfortunately, with increasing Ga 3+ content, thermally induced ionization of an electron from 5d 1 state to the conduction band becomes feasible around room temperature due to the reduction of ionization energy barrier, 18 which deteriorates the scintillation efficiency. [19][20][21][22] Further optimization was achieved by "energy level positioning" strategy through the Gd 3+ admixture. 19,23 Specifically, upon the Gd 3+ admixture the 5d 1 level moves downward and can compensate the upward shift and resulting negative effect due to Ga 3+ admixture.…”

mentioning

confidence: 99%

Origin of improved scintillation efficiency in (Lu,Gd)3(Ga,Al)5O12:Ce multicomponent garnets: An X-ray absorption near edge spectroscopy study

Luo

Nikl

et al. 2014

APL Materials

Self Cite

View full text Add to dashboard Cite

In the recent successful improvement of scintillation efficiency in Lu3Al5O12:Ce driven by Ga3+ and Gd3+ admixture, the “band-gap engineering” and energy level positioning have been considered the valid strategies so far. This study revealed that this improvement was also associated with the cerium valence instability along with the changes of chemical composition. By utilizing X-ray absorption near edge spectroscopy technique, tuning the Ce3+/Ce4+ ratio by Ga3+ admixture was evidenced, while it was kept nearly stable with the Gd3+ admixture. Ce valence instability and Ce3+/Ce4+ ratio in multicomponent garnets can be driven by the energy separation between 4f ground state of Ce3+ and Fermi level.

show abstract

mentioning

confidence: 99%

Origin of improved scintillation efficiency in (Lu,Gd)3(Ga,Al)5O12:Ce multicomponent garnets: An X-ray absorption near edge spectroscopy study

Luo

Nikl

et al. 2014

APL Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…Here we can also find the increasing intensity of broadband absorption 200-350 nm after air-annealing, and the band can be attributed to the Ce -O 2-charge transfer(CT) absorption band in our experiment does not show the same features with that given in the literature, it may be due to that the samples co-doped with divalent ions lead to more amount of stable Ce 4? , thus more stronger absorption around 260 nm in the Ca 2? , Mg 2? , B 2? codoped hosts [21,28,29].…”

Section: Resultsmentioning

confidence: 99%

Effect of thermal annealing on scintillation properties of Ce:Gd2Y1Ga2.7Al2.3O12 under different atmosphere

Wang

Ding

et al. 2017

Appl. Phys. A

Self Cite

View full text Add to dashboard Cite

Cerium-doped 1% Ce:Gd 2 Y 1 Ga 2.7 Al 2.3 O 12 (-GYGAG) single crystal samples grown via Czochralski method were annealed under air, O 2 and N 2 atmospheres from 350 to 1400°C. The X-ray excited luminescence spectra, energy spectra and UV as well as thermally stimulated luminescence (TSL) spectra were performed comparatively on ''as-grown'' and thermally annealed samples. It was found that the luminescence efficiency after annealing in air and O 2 was significantly enhanced compared to the non-annealed samples and this phenomenon was suggested to be caused by the existence of some oxygen vacancies in the Ce:GYGAG crystals. And the oxygen vacancies in the as-grown GYGAG crystals can be effectively eliminated by means of annealing in O 2 containing atmosphere without changing the luminescence mechanism. From the TSL curves before and after annealing, three traps within 77-650 K were found to be related to oxygen vacancies.

show abstract

“…Other examples in which TSL measurements are used to determine the position of the 5d excited levels with respect to the conduction band of Ce 3+ are given by Babin et al [74] and Wu et al [75]. …”

Section: Thermoluminescence As a Research Toolmentioning

confidence: 99%

Thermoluminescence as a Research Tool to Investigate Luminescence Mechanisms

Bos

2017

Materials

219

View full text Add to dashboard Cite

Thermally stimulated luminescence (TSL) is known as a technique used in radiation dosimetry and dating. However, since the luminescence is very sensitive to the defects in a solid, it can also be used in material research. In this review, it is shown how TSL can be used as a research tool to investigate luminescent characteristics and underlying luminescent mechanisms. First, some basic characteristics and a theoretical background of the phenomenon are given. Next, methods and difficulties in extracting trapping parameters are addressed. Then, the instrumentation needed to measure the luminescence, both as a function of temperature and wavelength, is described. Finally, a series of very diverse examples is given to illustrate how TSL has been used in the determination of energy levels of defects, in the research of persistent luminescence phosphors, and in phenomena like band gap engineering, tunnelling, photosynthesis, and thermal quenching. It is concluded that in the field of luminescence spectroscopy, thermally stimulated luminescence has proven to be an experimental technique with unique properties to study defects in solids.

show abstract

Thermally induced ionization of 5d1 state of Ce3+ ion in Gd3Ga3Al2O12 host

Cited by 36 publications

References 36 publications

Origin of improved scintillation efficiency in (Lu,Gd)3(Ga,Al)5O12:Ce multicomponent garnets: An X-ray absorption near edge spectroscopy study

Origin of improved scintillation efficiency in (Lu,Gd)3(Ga,Al)5O12:Ce multicomponent garnets: An X-ray absorption near edge spectroscopy study

Effect of thermal annealing on scintillation properties of Ce:Gd2Y1Ga2.7Al2.3O12 under different atmosphere

Thermoluminescence as a Research Tool to Investigate Luminescence Mechanisms

Contact Info

Product

Resources

About