TITLE:
Study on Laser Conditioning Parameters of HfO2/SiO2 Mul tilayer Mirrors
AUTHORS:
Fu Dai, Wenqing Shi, Baojian Yang, Wuchao Huang
KEYWORDS:
Laser-Conditioning, Defect, Laser Beam Increment, High Reflective Coatings
JOURNAL NAME:
Advances in Materials Physics and Chemistry,
Vol.7 No.6,
June
15,
2017
ABSTRACT: Laser conditioning is an effective method to improve
the laser damage threshold of HfO2/SiO2 multilayer films
prepared by electron beam evaporation. In this paper, some parameters that can
affect the efficiency of laser conditioning were discussed. The result is that the
maximum conditioning fluence should
be less than 90% of its unconditioned laser induced damage threshold (LIDT) to
avoid damage to the film. The laser beam increment between pulses and laser
conditioning steps has a
great influence on the improvement of damage threshold of HfO2/SiO2 multilayer high reflective coatings. The coverage
of the light intensity on the defect should be as wide as possible, and the
irradiation of light intensity should be as high as possible. The main
mechanisms of laser conditioning of HfO2/SiO2 multilayer
high reflective coatings may be the removal of Hf, Si and O ions and the
removal of the defects in the films.