کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5442842 | 1510768 | 2017 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
EPR and luminescence studies of the radiation induced Eu2+ centers in the EuAl3(BO3)4 single crystals
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی مواد
سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
We have studied the X-ray irradiated EuAl3(BO3)4 single crystals by means of luminescence and electron paramagnetic resonance (EPR) spectroscopy. It was found that the X-ray irradiation modifies the color of the EuAl3(BO3)4 crystal and leads to the formation of a stable Eu2+ centers from the Eu3+ centers located in a host matrix. Annealing of the crystal at 600 °C leads to the restoration of the original color and the disappearance of Eu2+ centers. The EPR and luminescence spectra of the Eu2+ ion were studied in a wide temperature range. The angular dependence of Eu2+ EPR spectra is described by an axial spin Hamiltonian characterized by the spin of S = 7/2 with the following parameters: gz = gx = 1.991 (1); b20 = â267,86 (16)*10â4cmâ1; b40 = â4,20 (8)* 10â4cmâ1; b60 = 0,37 (13)* 10â4cmâ1; A (151) = 31,4 (3)* 10â4cmâ1; A (153) = 13,9 (3)* 10â4cmâ1. Based on the comparison of spin Hamiltonian parameters of Eu2+ and Gd3+ ions, it was concluded that Eu2+ ion located at the Eu3+ site in the EuAl3(BO3)4 crystal lattice. Within the framework of the superposition model, the distortions introduced to the local environment by the Eu2+ and Gd3+ ions were analyzed. In the luminescence spectra, the bands associated with the Eu2+ and Eu3+ ions are detected. The photoluminescence decay kinetics of Eu3+-related emission (614 nm) has a single-exponential character, whereas the Eu2+-related band (323 nm) possess more complicated decay kinetics behavior that may point to the Eu2+ excited state ionization and its delayed recombination.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Optical Materials - Volume 66, April 2017, Pages 428-433
Journal: Optical Materials - Volume 66, April 2017, Pages 428-433
نویسندگان
A.A. Prokhorov, L.F. Chernush, V. Babin, M. Buryi, D. Savchenko, J. LanÄok, M. Nikl, A.D. Prokhorov,