| Autor: |
Song, Hongwei, Lu, Shaozhe, E, Shulin, Gao, Renxi, Zhang, JiaHua, Chen, Baojiu, Xia, Haiping, Zhang, Jianlin, Ni, Qiuhua |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 3/1/2002, Vol. 91 Issue 5, p2959, 6p, 2 Charts, 10 Graphs |
| Abstrakt: |
Optical absorption, fluorescence, excitation and time-resolved spectra, and fluorescence dynamics were studied in Eu[sup 2+] - and Eu[sup 3+]-codoped aluminosilicate glasses. The results indicated that the energy transfer occurred between Eu[sup 2+] and Eu[sup 3+] ions, in which the energy corresponding to the 4f[sup 6]5d to [sup 8]S[sub 7/2] transition of Eu[sup 2+] ions caused excitation of the Eu[sup 3+] ions to the [sup 5]D[sub J] level. Some of the electrons in the ground state [sup 7]F[sub 0] were thermally excited into the [sup 7]F[sub 1] state at room temperature, and thermal populations of the [sup 7]F[sub 1] level had great effects on the spectral shape of the [sup 5]D[sub 0]-[sup 7[sub 2]F[sub 2] emission. The effect of light irradiation at different wavelengths on fluorescence was systemically studied. The visible, ultraviolet and x-ray irradiation caused a decrease in the fluorescence of Eu[sup 2+] and/or Eu[sup 3+] ions. Frequency selective excitation experiments were performed at 10 K and room temperature. Instead of forming a spectral hole, the intensity of the [sup 7]F[sub 0] - [sup 5]D[sub 0] transition decreased as a whole. This was attributed to the interaction of Eu[sup 3+] ions with the two-level systems existing in the glass network. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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