Neodymium-doped phosphate laser glasses are the laser glass materials which were developed relatively early

and used in the fields such as nuclear fusion

high power laser amplifier and optic fiber laser and so on in China. But we are in trouble all the time

because the high thermal expansion coefficient leads to bad thermal and chemical stabilities and low-heat mechanical intensities. The thermal stability is very important to laser glasses and it is emphasis point in my work. By changing the composition of glass such as adding Al

2

O

3

the thermal expansion coefficient of the sample dramatically decreases

and the thermal expansion coefficient of the glasses in this work achieves α=38.75×10

-7

/℃. Transition temperature

T

f

and softening temperature

T

g

of the glasses are 684℃ and 605.5℃ respectively. Introducing of F

2

in glasses and improving preparation technology not only can get rid of Pt and water molecular

but also decrease phonon energy of glasses

at the same time

improve phonon efficiency and optimize spectroscopic properties. Fluorescence and absorption spectra and thermal expansion coefficient of Nd

3+

-doped phosphate laser glasses are tested at room temperature. Spectroscopic parameters of Nd

3+

-doped phosphate laser glasses were calculated according to their absorption spectrum. The transitions of Nd

3+

from

4

F

3/2

to

4

I

11/2

and from

4

F

3/2

to

4

I

13/2

are corresponding to fluorescence wavelength 1056 and 1321 nm respectively under the excitation of 514 nm argon ions laser at room temperature. Generally

quantum efficiency of energy level transition are determined by the phonon energy of substrate to large extent. The more phonon energy

the stronger multi-phonon non-radiation relaxation

so the smaller quantum efficiency is corresponding to the weaker fluorescence intensity. To decrease phonon energy of glass substrate

introducing F

2

in glasses can improve phonon efficiency and enlarge bandwidth of fluorescence spectral line. All the researches extend the application range of neodymium-doped phosphate laser glasses.