THE COMPUTATION OF LOWER BOUNDS FOR THENORM OF THE INDEX OF REFRACTION INAN ANISOTROPIC MEDIA FROM FAR FIELD DATA

摘要

We consider the scattering of time harmonicelectromagnetic plane waves by a bounded, inhomogeneous,anisotropic dielectric medium and show that under certain as-sumptions a lower bound on the norm of the (matrix) index ofrefraction can be obtained from a knowledge of the smallesttransmission eigenvalue corresponding to the medium. Nu-merical examples are given showing the efficaciousness of ourestimates.