Biomedical Engineering Reference
In-Depth Information
Excitation and emission spectra of Eu-Al co-doped silica glass.
30
3.7
Excitation spectra for the
5
D
0
7
F
2
transition of Eu
3+
ions in (a) SiO
2
3.8
and (b) Al
2
O
3
-SiO
2
glasses.
30
500 nm range of the Eu-Al co-doped glasses densified at 1125
C in air is
shown in Fig. 3.6. The spectrum shows a broad peak around 266 nm that is
attributed to a transition of the Eu
2+
ions from 4f
7
to 4f
6
5d (t
g
). The
emission and excitation spectra of the Eu-Al co-doped sample at 1125
8
C are
shown in Fig. 3.7. The emission shows a broad intense peak at 435 nm. A
qualitative measurement based on the emission intensity and the absorption
coefficient of these glasses shows that a maximum of 85% of the Eu
3+
ions
were converted to Eu
2+
ions. Figure 3.8 shows the excitation spectra for the
8
