少模光纤中受激布里渊散射的慢光

Slow Light of Stimulated Brillouin Scattering in Few-mode Fibers

利用全矢量有限元法计算了少模光纤中模内和模间受激布里渊散射各模式布里渊频移和布里渊增益谱,模拟了泵浦功率、有效传输长度及脉冲宽度对各模式慢光时间延迟量、脉冲展宽因子的影响.模拟结果表明:少模光纤中不同传输模式产生的受激布里渊散射慢光特性不同,输入泵浦功率及有效传输长度越大,各模式的慢光时延量、展宽越大,且当输入泵浦功率相同时,模内的慢光时延量、展宽因子均大于模间的.优化参数可得,在输入泵浦功率为0.5W,光纤有效长度为1km的条件下,LP01-LP01、LP11-LP11及LP01-LP11模式的时间延迟量分别为643.7ns、362.6ns和213.2ns,其展宽因子分别为1.346、1.207和1.126.

Brillouin frequency shift and Brillouin gain spectrum of different modes in few mode fiber were calculated by full vector finite element method.In addition,the influences of pump power,effective transmission length and pulse width on the slow-light time delay and pulse broadening factor of different modes in few mode fiber were also simulated.The simulation results show that characteristics of tunable slow light of different modes in the FMF are different,the larger time delay and pulse broadening factor of different modes are achieved as pump power and effective transmission length increasing,the time delay and pulse broadening factor of intramodal stimulated Brillouin scattering are greater than intermodal stimulated Brillouin scattering for a given input pump power.By critical tuning parameters,the time delay of LP 01-LP 01,LP 11-LP 11 and LP 01-LP 11 mode pairs are respectively 643.7 ns,362.6 ns and 213.2 ns at a given input pump power of 0.5 W and the effective fiber length of 1 km,pulse broadening factors are 1.346,1.207 and 1.126,separately.