Photoluminescence, thermoluminescence and defect centres in Y_2O_3 and Y_2O_3:Tb~(3+) under 100 MeV swift Ni~(8+) ion beam irradiation

摘要

Y2O3 and Y2O3:Tb3+ powders, synthesized via the solution combustion method, were studied in order to determine the effect of 100 MeV swift Ni8+ ions on the photoluminescence (PL), thermoluminescence (TL) and swift ion beam induced defects. Synthesized materials were characterized by X-ray powder diffraction, electron spin resonance, PL intensity, decay measurements and TL. Cubic structures were observed in both the pristine and ion irradiated materials. The ion irradiated materials exhibited smaller crystallite sizes than that of the pristine material. PL peaks in the visible region were identified at 485, 542, 582 and 621 nm due to the D-5(4)- F-7(3,4,5,6) transition of Tb3+. The PL intensity showed an increase up to 3 x 10(10) ions cm(-2) and then a significant decrease with a further increase in the ion fluence. The recorded time resolved PL at an ion irradiated fluence of 3 x 10(10) ions cm(-2), exhibited an increase in the life time of the material. n. glow curves were obtained for the samples irradiated with a swift NO8+ ion beam. These glow curves showed a peak at 518 K with a shoulder peak at 473 K and its intensity linearly increased upto a fluence of 1 x 10(11) ions cm(-2). Whereas, the undoped sample showed peaks at 421 and 662 K and its intensity sub-linearly increased upto a fluence of 1 x 10(11) ions(-2). TL efficiency values of the Y2O3:Tb3+ sample, irradiated by a 100 MeV Ni8+ ion beam, have been measured relative to the undoped Y2O3 sample and were found to be 1.34. The Tb3+ doped sample exhibited a less fading effect under the swift heavy ion beam.