贝塞尔-高斯脉冲光束在色散介质中的时间和光谱特性

对等衍射长度贝塞尔-高斯脉冲光束在色散介质中的时间和光谱特性作了研究，结果表明，通过选择适当的空间参数，贝塞尔-高斯脉冲光束沿轴上传输时，脉冲宽度不变。传输距离小于无衍射长度时，随衍射角增加，功率谱形状未变，脉冲波形保持不变；传输距离大于无衍射长度时，随衍射角增加，光谱由蓝移变为红移，脉冲展宽。

Temporal and spectral properties of Bessel-Gauss pulsed beams in dispersive media

The temporal and spectral properties of Bessel-Gauss pulsed beams with constant diffraction length in a linear dispersive medium are studied. It is shown that by a suitable choice of the spatial parameter β, Bessel-Gauss pulsed beams propagate along the axis without noticeable pulse broadening. If the propagation distance is smaller than the diffraction-free range, temporal pulse forms and normalized power spectra remain unchanged as the diffraction angle increases. However, if the propagation distance is larger than the diffraction-free range, the pulse duration broadens, and the spectra change from blueshifts to redshifts with the increasing diffraction angle.