ABSTRACT
Assuming that these media can sustain monochromatic plane waves, propagating in any direction the field vectors ,nk ke=
G G ,E HG G and DG may be given the harmonic representation (20.8) that reads )(0
(22.2) Substituting the operator relations (20.10), Eqs.(22.1) take the form
0k E Hµ ω× = G G G
k H Dω× = −G G G (22.3)
0=⋅ Hk GG 0=⋅ Dk GG which shows that H
G and D
G are always perpendicular to k
G and to each other. Thus both
lie in the wavefront, whereas, in general, E G
is not perpendicular to the wave vector, as highlighted by Eqs.(20.11) for an isotropic medium. As Faraday's law (22.3) shows that H G
is normal to ,E G
the electric vector must be coplanar with D G
and k G
, and can be resolved into components parallel and perpendicular to ne
G ( )n n nE E e e= ⋅G G G G , ( )n nE E E e eπ = − ⋅G G G G G The transverse nature of electromagnetic waves is preserved with respect to H
G and ,D
G
as illustrated in Figure 22.1.
