The LEPL (Laser excited photo luminescence) spectra of LiYF

4

:Nd

3+

excited by 5145Å emission of an Ar

+

Laser

and its XEPL (X-ray excited photo-Luminescence) spectra were bcth studied for the first time. Based on the energy values of the stark levels at corresponding temperatures and referred to their polarization properties

the fluorescence lines were designated (derived from table 1 and table 2). The results are listed in table 3 and table 4.From this work

the foljowing conclusion can be made.(1) Both of LEPL and XEPL in LiYF

4

:Nd

3+

have been studied for the first time

especially.the short wavelength f lucres cence have been observed.(2) The polarization characteristics of LiYF

4

:Nd

3+

fluorescence emission have been studied

and magnetic dipole transitions hava been observed in the system.(3) A new strong fluorescence line (A

3

→Y

3

) close to R

2

→Z

1

fluorescence peak has been found in LiYF

4

:Nd

3+

.(4) It can be seen from table 3 and table 4

that many fluorescence peaks belong to ax type of spectra. Some Γ

5

6

T

7

8

transitions occur only in particular polarization(σorπ spectrum).For example

the peak 15064cm

-1

(π

E

1

(7

8)→X

3

(5

6)) in table 3 and the peak 26103cm

-1

(σ

M

1

(5

6)→Y

1

(7

8)) in table 4 are these cases. This is the feature of the transitions between kramer doublets.