Non-monotonous refractive index changes recorded in a phosphate glass optical fibre using 248nm, 500fs laser radiation

作者：Sozzi Michele^*; Rahman Aashia; Pissadakis Stavros

来源：Optical Materials Express, 2011, 1(1): 121-127.

DOI：10.1364/OME.1.000121

Results are presented on the photosensitivity behavior of a phosphate glass optical fibre using 248nm, 500fs laser radiation. Bragg grating exposures performed using a double phase mask interferometer and peak intensities of 0.37TW/cm(2), revealed that grating growth becomes nonmonotonic in terms of average and modulated refractive index changes, resembling the Type IIA photosensitivity behavior. Average refractive index changes greater than 10. 3 were measured after accumulated energy density doses of 6.5KJ/cm(2). The Bragg gratings inscribed maintained significant part of their strength up to 377 degrees C. Exposed and side- polished fibre samples were subjected to Knoop micro- hardness measurements for revealing that the irradiated glass undergoes significant volume dilation.

• 出版日期2011-5-1