A New Method for Locating the Poles of Green's Functions in a Lossless or Lossy Multilayered Medium

A new method is presented to locate the poles of the Green's functions for a general multilayered medium, whether lossy or lossless. The problem associated with the pole extraction is reduced to solve the contour integrals in the complex plane that are represented in terms of the spectral-domain transmission coefficients. With the help of Cauchy's theorem, the proposed method can accurately and rapidly find all surface wave poles with a few contour integrals. The numerical examples are performed to show the efficiency of the method.