Brillouin Gain Reduction Via B $_{2}$O $_{3}$ Doping

We present both modeling results and experimental data demonstrating that B
₂
O
₃
(boric oxide) can be used as an effective SBS-suppressive optical fiber codopant due to a very large acoustic damping coefficient. A Ge-containing fiber with ~6 wt% B
₂
O
₃
at room temperature has a Brillouin gain coefficient more than 4 dB lower than that of standard Ge-doped SMF. These B-doped fibers, unlike standard Ge-doped SMF, have Brillouin spectra that broaden with increasing fiber temperature. Modeling parameters (acoustic velocity, spectral width, etc.) for bulk B
₂
O
₃
based on a fit-to-data are provided. Modeling results for the B-Ge-Si oxide system indicate that the bulk material gain falls below 0.5×10
^-11
m/W at 1534 nm near the 1B
₂
O
₃
:4SiO
₂
molar composition.