EPR and TSL studies on MgB4O7 doped with Tm: role of BO32− in TSL glow peak at 470K

Radiation induced defects in BaBPO5:Ce and their role in thermally stimulated luminescence reactions: EPR and TSL investigations

“…The EPR signals due to different radicals were separated using different microwave powers (microwave power saturation) and their thermal stabilities. The free radicals formed during the radiolysis were identified on the basis of their g factors, hyperfine coupling constants ( 11 B, I = 3/2, natural abundance 81% and 31 P, I = 1/2, natural abundance 100% and 16 O, I = 0, 100% abundance). The EPR parameters for different radical ions formed on irradiation of sample S 1 and S 2 are listed in Table 1.…”

“…To augment the process taking place in thermally stimulated luminescence (TSL), extensive work has been reported from our laboratory on several inorganic phosphors doped with lanthanide/actinide ion, by carrying out electron paramagnetic resonance (EPR) and/or and photo acoustic spectroscopy (PAS), wherever feasible [15][16][17][18]. In case of SrBPO 5 :Eu 2+ , it was suggested [1] that the recombination between the trapped electrons at anion vacancies (F centers) and the hole trapped centers in the vicinity of the impurity center (Eu 2+ ) are mainly responsible for the photo stimulated luminescence emission at 390 nm;, however, the electrons and hole trapped were not identified in these studies.…”

Thermoluminescence properties of lithium magnesium borate glasses system doped with dysprosium oxide

“…The TL mechanism in magnesium tetraborate doped with rare earth elements (MTB: RE 3+ ) was reported separately by Porwal and Annalakshmi . They identified defect centers such as borate radical (BO 3 ) 2− and oxygen vacancy , which are formed during gamma irradiation and established a mechanism for the TL process.…”

“…In the past two decades, rare earth (RE) ion-doped borate materials have been intensively explored for use in dosimeters (1,(4)(5)(6)(7)(8)(9)(10). Since its inception, this RE doped borate material exhibiting superior TL response, close tissue equivalent and excellent sensitivity have received much attention (11).…”

Spectroscopic and luminescence studies of thulium doped strontium borate glass

“…Rare earth doped borate materials have found application in Plasma Display Panels as red emitting phosphor ((Y,Gd)BO 3 :Eu), UV emitting medical lamps (SrB 4 O 7 :Eu), as green-emitting phosphor in fluorescent lamps (GdMgB 5 O 10 :Ce, Tb) [7]. For dosimetric application, alkali borates (Li, K) and magnesium borates have been extensively investigated [8][9][10][11][12][13]. Strontium tetraborate, SrB 4 O 7 , has a unique structural framework consisting of a three-dimensional (B 4 O 7 ) network of BO 4 tetrahedra, with Sr 2+ cations participating in SrO 9 polyhedra [14][15][16][17].…”