Erbium Doped Tellurite Glasses for Potential Infrared Sensor Applification

The B
₂
O
₃
was introduced into Er
³⁺
doped TeO
₂
-ZnO-Na
₂
O glass to increase the phonon energy of the host. The effect of B
₂
O
₃
on the lifetime of
⁴
I
_11/2
level was investigated. The results show that the lifetime of
⁴
I
_11/2
level is shortened ascribing to the increasing multiphonon decay rate between the
⁴
I
_11/2
and
⁴
I
_13/2
level. Accordingly, the green- and red-upconversion fluorescence decreases with increasing of B
₂
O
₃
concentration. A five-level rate-equation model of the Er
₃₊
population dynamics in tellurite glass is developed. The model suggests the green- and red-upconversion intensity is a quadratic dependence on the population density of the
⁴
I
_11/2
level. The intense visible upconversion fluorescence observed in Er
³⁺
doped TeO
₂
-ZnO-Na
₂
O glass indicates it can be used in infrared sensor application