Geoscience Reference
In-Depth Information
K
2
GdF
5
. These crystals may be a prospective material for solid-state lasers in the
range of 3
4
μ
m
[2]
.
Figure 8.5
shows the fluorescent emission spectrum and
the Pr(
1
G
4
!
3
H
5
)
fluorescent
lifetime for
transition in KGd
0.98
Yb
0.01
Pr
0.01
F
4
l
G
4
level is pumped directly at 1.02
when the
μ
m. In KGdF
4
, this transition is
centered near 1.3
μ
m and is broad enough for wavelength multiplexing, the life-
time is 150
s. Similar measurements have been made on KGd
0.98
Yb
0.01
Pr
0.01
F
4
and KGd
0.94
Yb
0.05
Pr
0.01
F
4
using three different pumping schemes: (i) pump Yb
(
2
F
7/2
!
μ
2
F
5/2
) at 0.94
μ
m and observed fluorescent emission at 0.97
μ
m from Yb
(
2
F
5/2
!
2
F
7/2
); (ii) pump Yb(
2
F
7/2
!
2
F
5/2
) at 0.970
μ
m and observe emission from
300
K
4
12 3456789
11580
11470
F
3/2
2
(a)
(c)
4280
4260
1
4
3 5 6
7
89
4152
4
4060
4015
3987
(b)
I
13/2
3860
1.30
1.34
1.38
λ
,
μ
m
Figure 8.4 Luminescence spectra (
4
F
3/2
!
4
I
13/2
) at (a) 77 K and (b) 300 K and (c) the
scheme of crystal field splitting of
4
F
3/2
and
4
I
13/2
transitions of Nd
3
1
ions in K
2
GdF
5
[4]
.
50
17
40
16
30
15
20
14
10
13
0
1.25
12
1.3
1.35
1.4
0
1
2
3
Wavelength (
μ
m)
Time (ms)
Figure 8.5 Fluorescent emission spectrum and fluorescent lifetime for the Pr(
1
G
4
!
3
H
5
)
transition in KGd
0.98
Yb
0.01
Pr
0.01
F
4
[5]
.
