Reflection from a Bianisotropic Dielectric

Abstract : The well-known surface densities of bound charge sigma = P dot n and current K = M x n, which give rise to discontinuities in fields at a surface, are inconsistent in their muitipole order. The electric quadrupole contribution is missing from each. A consequence of including this is the appearance of a surface density of electric dipole moment P. Its effect on the boundary conditions is derived, and a reflection experiment on a bianisotropic crystal is proposed, which in conjunction with a transmission experiment, allows the P contribution to be measured.