Radiation-induced infrared absorption in nuclear-pumped laser cavity components
Abstract
The transient transmission of laser activity cavity materials has been measured when they are subjected to 20 ms, fat, and nominal $3 nuclear radiation pulses from Sandia National Laboratories ACRR reactor. Infrasil and 7940 fused silica, and AR and high reflectance coatings have been transient tested at 1.06, 1.73, and 2.03 microns for gamma doses ranging from 0.3 to 0.65 Mrad and neutron fluences ranging from 4.0 to 1.5 10(sup 14) n/cm(sup 2). pulse widths range from 12 to 250 ms. Transient absorption in 7940 silica and the AR coatings is less than the noise for the conditions of this experiment. At the wavelengths listed above the upper bound for the absorption coefficient of 17940 is 0.00158 cm(sup -1) for single pulse operation. The reflectivity of the HR coating does not change when it is irradiated. Infrasil has both a transient and a permanent induced absorption when it is subjected to radiation. For single pulse operation the absorption coefficients at 1.06, 1.73, and 2.03 microns are 0.0115, 0.0026, and 0.0039 cm(sup -1), respectively.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- July 1992
- Bibcode:
- 1992STIN...9313249B
- Keywords:
-
- Gas Lasers;
- Infrared Absorption;
- Laser Cavities;
- Laser Materials;
- Laser Pumping;
- Neutron Irradiation;
- Radiation Effects;
- Silicon Oxides;
- Coatings;
- Fluence;
- Xenon;
- Lasers and Masers