UV laser induced inonization of silicon oxygen deficient centers (SODC) in silica glasses and germanium oxygen deficient centers (GODC) in germanosilicate glasses has been studied by direct displacement photocurrent measurements. For both SODC and GODC the two‐photon (two‐step) nature of photoionization has been established. The cross sections of transitions from first excited to upper (ionizable) states were estimated as σ12=6×10−18 cm2 for SODC and (0.5–1.0)×10−19 cm2 for GODC. The effect of pulse‐to‐pulse degradation of the photocurrent signal caused by the screening effect is applied to estimate the lifetimes and ranges of the free carriers. The conclusion was drawn, that ionized SODC and GODC play the key role for free charge trapping.

1.
K. O.
Hill,
B.
Malo,
F.
Bilodeau
, and
D. C.
Johnson,
Annu. Rev. Mater. Sci.
23
,
125
(
1993
).
Google Scholar
 
2.
P. St. J. Russell, J.-L. Archambault, and L. Reekie, Phys. World 41, (1993).
3.
R. Kashyap, Opt. Fiber Technol. 1, 17 (1994).
4.
W. W. Morey, G. Meltz, and W. H. Glenn, Opt. Photon. News 14, July (1990).
5.
V. B.
Neustruev,
J. Phys. Condens. Matter
6
,
6901
(
1994
).
Google Scholar
 
6.
V. N. Bagratashvili, A. O. Rybaltovskii, Ya. O. Simanovskii, and S. I. Tsypina, SPIE Proc. 1856, 69 (1993).
7.
V. A.
Radzig,
V. N.
Bagratashvili,
S. I.
Tsypina,
P. V.
Chernov
, and
A. O.
Rybaltovskii,
J. Phys. Chem.
99
,
6640
(
1995
).
Google Scholar
 
8.
V. N.
Bagratashvili,
S. I.
Tsypina,
V. A.
Radtsig,
A. O.
Rybaltovskii,
P. V.
Chernov,
S. S.
Alimpiev
, and
Y. O.
Simanovskii,
J. Non-Cryst. Solids
180
,
221
(
1995
).
Google Scholar
 
9.
V. N. Bagratashvili, S. I. Tyspina, S. S. Alimpiev, Y. O. Simanovskii, A. M. Prokhorov, and A. O. Rybaltovskii, Laser Chem. 12, 211 (1992).
10.
K.
Arai,
H.
Imai,
H.
Hosono,
J
Abe
, and
H.
Imagava,
Appl. Phys. Lett.
53
,
189
(
1988
).
Google Scholar
 
11.
R.
Kashyap,
G. D.
Maxwell
, and
D. L.
Williams,
Appl. Phys. Lett.
62
,
214
(
1993
).
Google Scholar
 
12.
V. N. Bagratashvili, V. K. Popov, S. I. Tyspina, P. V. Chernov, and A. O. Rybaltovskii, Opt. Lett. (in press).
13.
L.
Skuja,
J. Non-Cryst. Solids
149
,
77
(
1992
).
Google Scholar
 
14.
R. G.
Hughes,
Radiat. Eff.
26
,
225
(
1975
).
Google Scholar
 
15.
V. N. Bagratashvili, S. I. Tsypina, P. V. Chernov, A. O. Rybaltovskii, P. St. J. Russell, and L. Dong (unpublished).
This content is only available via PDF.
© 1996 American Institute of Physics.
1996
American Institute of Physics
You do not currently have access to this content.