【摘要】 为了研究光脉冲在掺镱光纤放大器中的放大传输特性,建立了光脉冲在分布式光纤放大器中的传输方程,采用分步傅里叶变换法数值模拟了其传输状态,并着重讨论了频率失谐对光脉冲特性的影响。结果表明:对于掺镱光纤放大器,随着在放大器中的传输,光脉冲在放大的同时被展宽,产生变形,其功率谱加宽;当出现频率失谐时,光脉冲的放大能力减弱,并且失去输入时的对称性。若光脉冲中心频率沿不同的方向偏离介质增益峰值频率,脉冲变形规律不同。因此在设计放大系统时应该考虑光纤放大器的色散、非线性效应以及频率失谐对光脉冲传输特性的影响。更多还原

【Abstract】 In order to study the amplification and propagation characteristics of optical pulse in ytterbium-doped fiber amplifier,the propagation equation of optical pulse in distributed fiber amplifier is established. Using split-step Fourier transform method,the propagation state of optical pulse is simulated,and influence of frequency detuning on characteristics of optical pulse is discussed especially.The results show that optical pulse is amplified and broadened simultaneously in ytterbium-doped fiber amplifier,so it has a deformed profile and a broadening power spectrum.For the case of frequency detuning,the amplification of optical pulse has declined and symmetry of the pulse dispears.If the center frequency of optical pulse deviates from the gain peak frequency in different directions,the deformation law of pulse is different.Therefore, the influence of dispersion and nonlinear effect of fiber amplifier and frequency detuning on the propagation characteristics of optical pulse should be considered in the design of amplification system.更多还原