Erbium-doped fiber amplifiers(EDFAs) with wide and flat gain spectra in telecommunication windows are the key issues for dense wavelength division multiplexing(DWDM) optical network systems.How-(ever)

the traditional commercialized EDFAs are made of SiO

2

-based material in which Er

3+

ions show a narrow (emission) bandwidth for the

4

I

13/2

→

4

I

15/2

transition.Many methods have been investigated to broaden and flatten the gain spectra of the traditional EDFAs in order to meet the capacity demand.Recently

tellurite glasses have received considerable attention in EDFAs for the broad bandwidth of over 70 nm

which meets the transmission capacity of DWDM systems.Nevertheless

the bad thermal stability and the high up-conversion become the(unsolvable) obstacle.Compared to tellurite

borate is a better glass-former compound and has higher(stability)

larger phonon energy and broad bandwidth.We prepared Er

3+

doped Bi

2

O

3

-B

2

O

3

-SiO

2

glasses according to the following molar composition: 40% Bi

2

O

3

20% B

2

O

3

40% SiO

2

and 3.0% Er

2

O

3

is added to dope the glasses.The absorption spectra for Er

3+

and OH

-

group

emission spectra and luminous decay for the transition

4

I

13/2

→

4

I

15/2

were measured.Accor-(ding) to the standard J-O procedure the intensity parameters for the Er

3+

in the prepared glass were obtained.The concentration of OH

-

group and inner quantum efficiency for

4

I

13/2

level were estimated.It is validated that the lower quantum efficiency is caused by the higher content of OH

-

group

about 3 times of Er

3+

(content.) On the base of McCumber theory

the stimulated emission cross section for the

4

I

13/2

level was derived and found to be in better agreement with the results calculated by using the emission spectra.We draw a conclusion that it is essential for the borate used in EDFAs to decrease the higher content of OH

-

group despite of higher stability

larger phonon energy and broad bandwidth.