ABSTRACT

We will present in this appendix, principally for the benefit of the less experienced reader, a derivation of the dispersion in a bianisotropic medium and the Fresnel coefficients across the interface between an isotropic medium and a bianisotropic medium. This is primarily to only demonstrate the manner of calculating them. By following the procedure the reader should be able to derive all the cases (anisotropic, bi-isotropic or bianisotropic) that (s)he would confront in the book. We will consider the case when the constitutive relations for the bianisotropic medium are given by

D = ε0

⎛ ⎝ εx 0 00 εy 0

0 0 εz

⎞ ⎠E + 1

c

⎛ ⎝0 iξxy 00 0 0

0 iξzy 0

⎞ ⎠H, (B.1)

B = 1 c

⎛ ⎝ 0 0 0iζyx 0 iζyz

0 0 0

⎞ ⎠E + μ0

⎛ ⎝ 1 0 00 μy 0

0 0 1

⎞ ⎠H. (B.2)

These relations are seen to be reciprocal if ζyx = −ξxy and ζyz = −ξzy. An array of split-ring resonators with their axes along the y direction (or cylinders along the y directions) would be well described by these constitutive relations (see Chapter 3). This is a special case of a bianisotropic medium where the modes in the medium are linearly polarized.