Open AccessFabrication of internal diffraction gratings in calcium fluoride crystals by a focused femtosecond laser
Author(s) -
Quanzhong Zhao,
Jianrong Qiu,
Xiongwei Jiang,
Chao Zhao,
Congshan Zhu
Publication year - 2004
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/opex.12.000742
Subject(s) - materials science , femtosecond , optics , refractive index , laser , diffraction , diffraction grating , fabrication , annealing (glass) , diffraction efficiency , optoelectronics , irradiation , absorbance , grating , medicine , physics , alternative medicine , pathology , nuclear physics , composite material
We report the fabrication of internal diffraction gratings in calcium fluoride crystals by a focused near-IR 800 nm femtosecond laser. The diffraction efficiency and refractive index change were evaluated after femtosecond laser irradiation and subsequent annealing. The maximum refractive index change was estimated to be 3.57x10(-4). Optical absorption spectra, measured for the crystals before and after the laser irradiation and subsequent annealing, indicate that the absorbance increase after femtosecond laser irradiation and decrease with increasing annealing temperature. The mechanisms of refractive index change are proposed. The results may be useful for fabrication of three-dimensional integrated optics devices in the crystals.