Raman study on silica optical fibers subjected to high tensile stress

Abstract

For silica (pure and synthetic) optical fibers, on which tensile stresses from 0 to 4 GPa were imposed, Raman studies were carried out. It has become evident by deconvoluting the silica Raman peaks that the main peak intensity at 440 cm−1 decreases with increasing stress while the peaks at 490, 604, and 800 cm−1 remain practically unchanged. The fact that the 490 cm−1 defect line was not affected by the stress applied to fibers is contrary to the conclusion by G. E. Walrafen, P. N. Krishnan, and S. W. Freiman [J. Appl. Phys. 52, 2832 (1981)]. The results obtained in the present study are rather extensively discussed from a microscopic view of silica glass networks.