Optical characteristics of virgin and proton-irradiated ceramics of magnesium aluminate spinel

Feldbach, E.; Kudryavtseva, Irina; Mizohata, Kenichiro; Prieditis, G.; Räisänen, J.; Shablonin, E.; Lushchik, A.

doi:10.1016/j.optmat.2019.109308

Cited by 27 publications

(20 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[20]), which generally underestimate this energy. In the same time, it is close to that 8.2 eV recently suggested for spinel single crystals, based on the analysis of low temperature (6 K) PL/PLE spectra [21][22]. The interband electronic transitions hn≥8.3 eV can be also seen in PLE spectra of all emissions of pristine MgAl 2 O 4 (Fig.…”

Section: Resultssupporting

confidence: 88%

“…5 to a localised exciton. The nature of the localisation sites still remains an issue, while very recent studies of the Tartu group [21][22] tentatively assigned them to antisite defects. The excitonic transitions at 7.8 eV were clearly observed in PLE spectra of UV2 and V2 bands, which indicates an effective energy transfer from exciton to respectively F centres and Mg 2+ defects.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Effects of Ta doping and irradiation with He+ ions on photoluminescence of MgAl2O4 spinel ceramics

Spiridigliozzi

Pille

Schoenstein

et al. 2020

Journal of the European Ceramic Society

View full text Add to dashboard Cite

Photoluminescence (PL) properties of pristine and Ta-doped MgAl 2 O 4 spinel ceramics prepared via spark plasma sintering technique and irradiated with He + ions were studied. The results indicate strong influence of the grain boundaries on PL spectra. Ta doping promotes the formation of O and Al vacancies at the grain boundaries leading to an increased number density of F + centres. The ionised irradiation forms antisites preferentially at the grain boundaries, which inhibit excitonic PL and exciton energy transfer while do not affect proper PL of lattice defects. A weak PL excitation band at 7.25±0.25 eV may belong to excitons localised near bulk antisites. In the Ta-doped ceramics, the electronic transitions between 5.75 eV and 7.0 eV belong to an intermediate state situated at the grain boundaries and structurally linked to Ta, which readily transfers energy to F and F + centres; it was assigned to the nucleated Mg 4 Ta 2 O 9 phase.

show abstract

Section: Resultssupporting

confidence: 88%

Section: Resultsmentioning

confidence: 99%

Effects of Ta doping and irradiation with He+ ions on photoluminescence of MgAl2O4 spinel ceramics

Spiridigliozzi

Pille

Schoenstein

et al. 2020

Journal of the European Ceramic Society

View full text Add to dashboard Cite

show abstract

“…As a result, large-and small-radius bound excitons coexist. Usually defects responsible for this kind of situation are of neutral type, which in our case is, most probably, neutral structural vacancies V Ge  [28]. The zerophonon line of the localized exciton X * -V Ge  was observed at 3.33 eV in the spectrally resolved CL (Fig.…”

Section: Resultsmentioning

confidence: 67%

Electronic Band Transitions in γ-Ge3N4

Feldbach

Zerr

Museur

et al. 2021

Electron. Mater. Lett.

Self Cite

View full text Add to dashboard Cite

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

show abstract

“…Xe/cm 2 (the stage is more obvious in case of the linear abscissa scale), while significantly higher rate of defect accumulation is typical of lower irradiation fluences. It is generally accepted (see, e.g., [39,40]) that a fast growing nonlinear component of dose dependence below Φ = 3.3 × 10 13 Xe/cm 2 can be explained by a partial creation of Ftype centers on the basis of already existing in the sample as-grown oxygen vacancies. At the same time, the second nonlinear stage of de-fect accumulation (saturation) due to the possible aggregation of single F-type centers (for instance, formation of F2 and more complex defects) is not reached even at the highest fluence of Φ = 3.3 × 10 14 ions/cm 2 .…”

Section: Resultsmentioning

confidence: 99%

“…In addition, a significant attenuation of a spectrally integrated CL has been recently detected in many WGMs exposed to irradiation with fast neutrons or swift ions [36,40,48,49]. Besides simple emission reabsorption by radiation-induced structural defects, this effect can be partly connected with radiation-induced strengthening of non-radiative processes under harsh radiation conditions.…”

Section: Resultsmentioning

confidence: 99%

Accumulation of radiation defects and modification of micromechanical properties under MgO crystal irradiation with swift 132Xe ions

Baubekova

Аkilbekov

Feldbach

et al. 2020

Nuclear Instruments and Methods in Physics Research Section B:

View full text Add to dashboard Cite

Accumulation of F-type defects under irradiation of MgO crystals by 0.23-GeV 132 Xe ions with fluence varying by three orders of magnitude has been investigated via the spectra of optical absorption and low-temperature cathodoluminescence. The number of single centers continuously increases with fluence without any marks of saturation. At the highest fluence, a mean volume concentration of 3.1 × 10 19 and 3.35 × 10 19 cm −3 is reached for F and F + centers, respectively. The F + emission strongly dominates in the cathodoluminescence of irradiated MgO and its enhancement with fluence is detected. However, the creation efficiency of theF2 aggregate centers is very low and fluence dependence has a complicated shape. Radiation-induced changes of micro-mechanical properties of the same samples have been analysed; the depth profiles of hardening correlate with the ion energy loss. A joint contribution of ionization and impact mechanisms in the formation of structural defects under MgO irradiation with Xe ions is considered.

show abstract

Optical characteristics of virgin and proton-irradiated ceramics of magnesium aluminate spinel

Cited by 27 publications

References 48 publications

Effects of Ta doping and irradiation with He+ ions on photoluminescence of MgAl2O4 spinel ceramics

Effects of Ta doping and irradiation with He+ ions on photoluminescence of MgAl2O4 spinel ceramics

Electronic Band Transitions in γ-Ge3N4

Accumulation of radiation defects and modification of micromechanical properties under MgO crystal irradiation with swift 132Xe ions

Contact Info

Product

Resources

About