Abstract In this paper, characteristics of tunable slow light of different modes based on intramodal stimulated Brillouin scattering in a few-mode fiber are calculated by the full-vector finite element method. In addition, the influences of doping concentration (GeO2 doped) on the effective refractive index, effective mode area, Brillouin frequency shift, Brillouin threshold, time delay and pulse broadening factor of each mode in the few-mode fiber are also simulated. The simulation results indicate that the effective mode area, Brillouin frequency shift and Brillouin threshold of each mode decrease with the increase of doping concentration, but time delay exhibits an opposite behavior. Time delay of LP01 mode is greater than that of LP11 mode for a given doping concentration. When the doping concentration increases from 1.2% to 2.4%, time delay of LP01 (LP11) mode increases from 291 ns (64 ns) to 384 ns (187 ns) at a given input pump power of 0.5 W and the effective fiber length of 2 km, meanwhile the corresponding broadening factor varies from 1.17 (1.04) to 1.22 (1.11).

中文翻译：

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掺杂对少模光纤中受激布里渊散射慢光的影响

摘要 本文采用全矢量有限元方法计算了基于模内受激布里渊散射的多模光纤中不同模式的可调谐慢光特性。此外，还模拟了掺杂浓度（GeO2掺杂）对少模光纤中各模的有效折射率、有效模面积、布里渊频移、布里渊阈值、时延和脉冲展宽因子的影响。仿真结果表明，各模式的有效模式面积、布里渊频移和布里渊阈值随着掺杂浓度的增加而减小，但时延表现出相反的行为。对于给定的掺杂浓度，LP01 模式的时间延迟大于 LP11 模式的时间延迟。当掺杂浓度从 1.2% 增加到 2.4% 时，