Dielectric atomic mirrors are considered in which the repulsive force field
owes its existence to an evanescent mode in the presence of a metallic cap
ping layer. The theory of such an atomic minor is constructed, assuming a f
inite thickness of the metallic layer with a finite plasma frequency and ad
opting the field-dipole orientation picture. The Rabi frequency together wi
th the reflectivity for the light incident from within the substrate are ev
aluated, and their variations with the type of metal and layer thickness an
alyzed as useful indicators of the effectiveness of the system as an atomic
mirror. A number of interesting features are pointed out, including a desi
rable enhancement. Solutions of the equation of motion for a given atom, su
bject to given initial conditions, lead to trajectories exhibiting reflecti
on. The leading force fields controlling the dynamics include the average d
ipole image force plus the average light-induced forces due to the evanesce
nt field. The parameters used to compute the trajectories are similar to th
ose in recent experiments in which Rb atoms incident on a silver film depos
ited on a glass substrate have been shown to experience enhanced mirror act
ion. The factors controlling the enhancement in general are pointed out and
discussed.