
35Defect-Induced Damage
Chapter 3
pulse length of τ ≫ a
2
/D
a
, an exact solution for the threshold F
0
given by Equation 3.4
can be simplied to (Lange etal., 1982, 1984)
F
T
CK
C
C
C
C
K
K
c
hh h
aa
hh
hh
aa
h
a
0
16
1
120
15
10=+−−
⎛
⎝
⎜
⎞
⎠
⎟
⎡
⎢
⎤
π
ρτ
πρ
ρ
ρ
ρ
⎥⎥
−1
.
(3.14)
Figure 3.6 shows the damage threshold for platinum impurity in glass as a function
of host conductivity and O
2
impurity in F
4
as a function of impurity conductiv-
ity (Lange etal., 1982) calculated using exact numerical (Equation 3.4) and approxi-
mate (Equation 3.14) solutions. One nds a weak threshold dependence on absorber
conductivity. Finite element analysis calculations (Papernov and Schmid, 1997) of ...