Insights into complex Berenger modes: a view from the weighted optical path distance perspective.

We present a simple and efficient approach for higher-order Berenger mode computation. We establish the physical mapping between radiation modes and complex Berenger modes, and theoretically prove that the higher-order substrate Berenger modes and cladding Berenger modes can converge to a cluster of complex modes with the same phase angle. This model can be explained by weighted optical path distance in both cladding and substrate, and can be …