Tellurite And Fluorotellurite Glasses For Active And Passive

6. Optical properties; MDO 216
6.2.1.3. Spectroscopy of Er +3 -doped composition
When a glass host which transmits in the NIR region is doped with erbium, emission
bands are seen in this region (around 1.5 µm) due to the large number of energy levels of
the Er +3 ion (such as 4 I15/2 4 I13/2). This phenomenon can be used to amplify signals
carried by the glass in this important telecommunications window. Doping of
fluorotellurite glass compositions was investigated here. The glasses were heat treated to
investigate possible modification of the erbium bands with time and temperature.
Fig. (6.44) shows the near-IR spectra of glass MOF017 (69.86TeO2-9.98Na2O-
19.96ZnF2-0.20ErF3 mol. %) as-annealed, and heat treated for 1 hour at 245, 255, 265
and 275°C.
Absoprtion coefficient / cm -1
0.11
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
Wavelength / µm
1.60 1.55 1.50 1.45
6200 6400 6600 6800 7000
Wavenumber / cm -1
Untreated
1 hr. 245 o C
1 hr. 255 o C
1 hr. 265 o C
1 hr. 275 o C
Fig. (6.44): Near-IR spectra of glass MOF017 (69.86TeO2-9.98Na2O-19.96ZnF2-
0.20ErF3 mol. %) untreated, and heat treated for 1 hour at 245, 255, 265 and 275°C.
110
100
90
80
70
60
50
40
30
20
10
0
Loss / dB.m -1