The new Er

3+

doped tellurite glass(70TeO

2

-9B

2

O

3

-6Nb

2

O

5

-5Na

2

O-10ZnO) was prepared by the technique of high-temperature melting.The spectral properties

such as absorption spectra and emission spectra of the glass sample have been measured and investigated.The Judd-Ofelt intensity parameters Ω

t

(

t

=2

4

6)(Ω

2

=8.01×10

-20

cm

2

Ω

4

=2.09×10

-20

cm

2

Ω

6

=1.15×10

-20

cm

2

)

transition probabilities

excited state lifetimes and the branching ratios have been predicted of several Er

3+

ions transitions based on the Judd-Ofelt theory.Compared with the other glass hosts

it found that the Ω

2

is bigger of Er

3+

in this tellurite glass

which shows that the covalency between the Er

3+

and O

2-

is stronger than silicate

germanate

fluorid

bismuthate

and phosphate glass.The transition probability of Er

3+

in this tellurite glass is about 492 s

-1

indicating that Er

3+

ions could have strong transition at 1.5 μm in tellurite glass.The broad 1.5 μm fluorescence was observed under 970 nm excitation

and its full width at half maximum(FWHM) is 73 nm.The emission cross-section was calculated according to the McCumber theory.The cross section was quite large due to a large refractive index of the host.The value of FWHM×σ

e

for Er

3+

in tellurite glass is more larger than that of the bismuth

phosphate

germinate and silicate glass.The results showed that the broad and flat

4

I

13/2

→

4

I

15/2

emission of Er

3+

ions around 1.5 μm can be uses as an potential optical amplifier for the wavelength-division-multiplexing(WDM) network system.