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IJPAP Vol.47 [2009] >
IJPAP Vol.47(06) [June 2009] >
| Title: | Role of defect centres in thermoluminescence mechanism of Tb3+doped MgAl2O4 |
| Authors: | Raja, E Alagu
Dhabekar, Bhushan
Menon, Sanjeev
More, S P
Rao, T K Gundu
Kher, R K |
| Keywords: | Thermoluminescence
MgAl2O4
Defect centres
Electron spin resonance |
| Issue Date: | Jun-2009 |
| Publisher: | CSIR |
| Abstract: | Magnesium aluminate (MgAl2O4) doped with terbium was prepared by combustion synthesis. Defect centres of MgAl2O4:Tb are studied by correlating various techniques such as Electron Spin Resonance (ESR), Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL). TL studies on MgAl2O4:Tb3+ show two TL peaks at 120 and 340°C. MgAl2O4:Tb3+ exhibits OSL when stimulated with 470 nm blue light. ESR study shows two defect centres with g = 2.011 and g = 2.0052 which are assigned to V- centre and F+ centre, respectively. Step annealing ESR technique study suggests that V-centre is correlated to 120°C TL peak whereas F+ centre is correlated with both the 120 and 340°C TL peaks. A TL mechanism is proposed. ESR–OSL correlation studies are carried out. The results of ESR-OSL correlation study along with TL bleaching study support the proposed TL mechanism of 120°C TL peak. |
| Page(s): | 420-425 |
| ISSN: | 0975-1041 (Online); 0019-5596 (Print) |
| Source: | IJPAP Vol.47(06) [June 2009]
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