光子学报, 2010, 39 (8): 1528, 网络出版: 2010-09-25
高功率超短脉冲在增益介质中的传输特性
Propagation Properties of High Power Ultrashort Pulse in the Gain Medium
高功率 超短脉冲 传输特性 分步傅里叶变换法 增益色散 High power Ultrashort pulse Propagation property Split-step Fourier transform method Gain dispersion
摘要
在考虑了增益介质的群速度色散、克尔非线性效应、增益饱和和增益谱后,推导出了光脉冲在介质中的传输方程.采用分步傅里叶变换法数值模拟了高功率线性啁啾脉冲在增益介质中的传输状态,并着重讨论了增益色散对光脉冲形状和功率谱的影响.计算结果表明:当高功率超高斯光脉冲在增益介质中传输放大时,脉冲形状变得尖锐,峰值向脉冲前沿移动;功率谱峰值向低频方向移动,并且在功率谱边缘形成非对称振荡结构;当介质的增益色散增大时,光脉冲光谱宽度变窄,峰值功率减小,因此对于宽光谱脉冲,增益色散将会导致损耗.
Abstract
Taking the group velocity dispersion, Kerr nonlinear effects, gain saturation and gain spectrum of gain medium into account, a equation describing the propagation of optical pulse in the medium is derived. The propagation state of a high power linear chirped pulse in the gain medium is simulated numerically using Split-step Fourier transform method, and the influence of gain dispersion on the profile and power spectrum of optical pulse is discussed emphatically. The results show that when propagating and amplified in the gain medium, the high power super-Gaussian optical pulse′s shape becomes sharp, peak moves to pulse front edge, the spectral peak moves to lower frequency, and the asymmetric oscillation structure is formed in spectral edge. When the gain dispersion of medium increases, the spectrum width of optical pulse becomes narrow, and its peak power decreases. As a result, the gain dispersion will cause loss of the broadband spectrum pulse.
周小红, 王泽勇, 王黎, 高晓蓉, 罗斌. 高功率超短脉冲在增益介质中的传输特性[J]. 光子学报, 2010, 39(8): 1528. ZHOU Xiao-hong, WANG Ze-yong, WANG Li, GAO Xiao-rong, LUO Bin. Propagation Properties of High Power Ultrashort Pulse in the Gain Medium[J]. ACTA PHOTONICA SINICA, 2010, 39(8): 1528.