摘要
采用复数波数定义和衍射积分方法,研究了啁啾高斯脉冲在增益色散介质中的传输特性,给出了介质增益谱为洛仑兹分布时的频谱分布以及时空分布的传输解析公式,详细分析了传输过程中光场的频谱和时空分布、脉宽和频谱变化以及谱移等特性。结果表明,啁啾高斯光束在介质中传输时其时间波形仍保持高斯分布不变,但在传输过程中其脉宽会发生变化。在传输过程中,啁啾参量会影响谱宽的减小程度以及谱移的幅度。啁啾参量越大,脉宽展宽和谱宽压窄的效果越明显,同时,随着传输距离的增大,光谱谱移也越明显。对于给定的啁啾参量,随着传输距离的增大,谱移将最终趋于一恒定值。
The propagation properties of the chirped Gaussian pulse through gain-dispersion medium are studied by using the definition of complex wave number and the method of diffraction integral. The analytical expressions for the spectrum distribution and the temporal-spatial distribution of the chirped Gaussian pulse are given for the case of the gain-spectrum of Lorentzian distribution. The propagation properties, such as the spectrum distribution, temporal-spatial distribution, variations of the pulse width and the spectrum width, as well as the spectrum shift, ere, were analyzed in detail. It is shown that the pulse still keeps the Gaussian shape in temporal domain when the chirped Gaussian pulse propagates in the gain-dispersion medium, whereas the pulse will undergo the variation of the pulse width. During the propagation, the decrease of the spectrum width and the spectrum shift can be influenced by the chirped parameter. The larger the chirped parameter is, the more obvious the effects of broadening of pulse width and compression of spectrum width are. Furthermore, the spectrum shift increases with the propagation distance. For the given chirped parameter, the spectrum shift will tend to be a constant along the propagation distance.
出处
《光学与光电技术》
2009年第4期11-14,共4页
Optics & Optoelectronic Technology
基金
教育部新世纪优秀人才支持计划(NCET-05-0784)
四川省青年科技基金(05ZQ026-013)资助项目
关键词
啁啾
增益色散
谱移
脉冲展宽
增益窄化
chirped
gain-dispersion
spectrum-shift
pulse broadening
gain narrowing
