  We study the possibility of creating spatial patterns having subwavelength
size by using the so-called dark states formed by the interaction between atoms
and optical fields. These optical fields have a specified spatial distribution.
Our experiments in Rb vapor display spatial patterns that are smaller than the
length determined by the diffraction limit of the optical system used in the
experiment. This approach may have applications to interference lithography and
might be used in coherent Raman spectroscopy to create patterns with
subwavelength spatial resolution.
