کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5401139 | 1505926 | 2013 | 13 صفحه PDF | دانلود رایگان |

The paper presents the results of the study on luminescence and electronic excitations in Li6Gd(BO3)3 single crystals. The optical and luminescence spectroscopy with a sub-nanosecond time resolution upon selective photoexcitation in the energy range from 3.0 to 650Â eV was used to investigate in detail the luminescence of both the Gd3+ host ions and Ce3+ impurity ions as well as the processes of energy transfer between them. The intrinsic ultraviolet emission at 3.95-3.97Â eV due to Pj6âS7/28 transitions in the Gd3+ host ion and the fast luminescence at 2.8-3.0Â eV due to 5dâ4f1 dipole-allowed transitions in the Ce3+ impurity ion were studied upon excitations through the intracenter, charge transfer, band-to-band, and inner-shell transitions. The specificity of the energy transfer upon excitation of photoluminescence in the energy range of absorption of the inner shells of different atoms of the crystal, as well as in the energy region of the giant resonance of 4d-4f transitions was revealed. On the basis of the experimental data, the bandgap Eg=9.3Â eV, the minimum energy of the 5dâ4f1 and charge transfer transitions were determined. The expected positions of the ground states of the 4fn and 4fnâ15d levels of trivalent lanthanide ions as well as the 4fn+1 and 4fn5d levels of divalent ions were calculated for all the lanthanide ions in Li6Gd(BO3)3 host crystal.
⺠We studied PL of Li6Gd(BO)3 (LGBO) crystals upon excitations from 3 to 650 eV. ⺠We studied energy transfer at f-f, f-d, CT, band-to-band, and inner-shell transitions. ⺠We studied excitation mechanisms for intrinsic Gd3+ and impurity Ce3+ emissions. ⺠We determined band gap Eg=9.3 eV, energies of 5d-4f and CT transitions. ⺠We determined absolute energy locations of lanthanide ions in LGBO crystal.
Journal: Journal of Luminescence - Volume 134, February 2013, Pages 113-125