Pulsed beam propagation in plane stratified media: Asymptotically exact solutions
Pulsed beam propagation in plane stratified media: Asymptotically exact solutions
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平面分层介质中的脉冲束传播：渐近精确解
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
E. Heyman
中科院分区：
文献类型：
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作者：
Y. Kaganovsky;E. Heyman
脉冲波束在一般非均匀介质中传播的封闭解可以通过沿弯曲传播轨迹的近轴波跟踪得到。作为验证这些解的实验平台，我们在这里导出了一般平面分层介质中PB的渐近精确解。这种解可以通过复源（CS）方法得到，但这需要将非均匀波速扩展到复坐标空间。为了克服这一困难，我们使用了一种广义平面波表示，其中CS场用作孔径平面的初始条件。然后通过瞬态谱理论（STT）计算三维PB场的谱积分，该理论将场表示为瞬态平面波的谱积分，可以压缩为简单紧凑的一维积分。
Closed form solutions for pulsed beam (PB) propagation in general inhomogeneous media can be obtained via paraxial wave tracking along the curved propagation trajectories. As a test bed to validate these solutions, we derive here an asymptotically exact solution for a PB in a general plane stratified medium. Such a solution can be derived via the complex source (CS) approach, but this requires an extension of the inhomogeneous wave-speed to the complex coordinates space. To circumvent this difficulty, we use a generalized plane-wave representation in which the CS field is used as the initial condition in the aperture plane. The spectral integral for the 3D PB field is then evaluated via the spectral theory of transients (STT) which expresses the field as a spectral integral of transient plane-waves that can be contracted to a simple and compact 1D integral.