The
phenomenon of enhanced backscattering in the scattering of light from
a randomly rough surface is the presence of a well-defined
peak in the retroreflection direction in the angular dependence of
the intensity of the light scattered diffusely from the surface.
A striking feature of this phenomenon is that it occurs
for any angle of incidence. Suppose, however, that one would
like to have a random surface that displays enhanced backscattering
for only a single, specified, angle of incidence. Such a
surface could be useful, for example, in situations where one
wishes to position a source (and hence the detector) at
a specified direction with respect to the site at which
the scattering surface is situated. In this paper we show
how a one-dimensional random surface can be generated that produces
an enhanced backscattering peak for only a specified angle of
incidence when illuminated by p-polarized light whose plane of incidence
is perpendicular to the generators of the surface. This surface
is defined by a power spectrum (the Fourier transform of
the surface height autocorrelation function) given by g(Q) = (

)/(4(

)k)[
(Q-k
1+

k)

(k
1+

k-Q)+

(Q-k
2+

k-Q)

(k
2+

k-Q)+

(-Q-k
1+

k)

(k
1+

k+Q)+

(-Q-k
2+

k)

(k
2+

k+Q)], where

(z) is the Heaviside unit
step function, k
1= k
R-k
0,k
2=k
R-k
0,k(subscriptR is the real part of the
wavenumber of the surface plasmon polariton of frequency

supported
by the planar vacuum-metal interface, and k
0 is related to
the angle of incidence measured clockwise from the x
3-axis by
k
0=(

/c)sin
0. An explanation is provided for why a surface defined
by this power spectrum produces enhanced backscattering at only the
angle of incidence given by
s=-
0, and it is confirmed
by numerical calculations of the angular dependence of the intensity
of the light scattered diffusely from it.
©2003
COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.