A NERS-active structure is disclosed that includes at least one
heterostructure nanowire. The at least one heterostructure nanowire may
include alternating segments of an NERS-inactive material and a
NERS-active material in an axial direction. Alternatively, the
alternating segments may be of an NERS-inactive material and a material
capable of attracting nanoparticles of a NERS-active material. In yet
another alternative, the heterostructure nanowire may include a core with
alternating coatings of an NERS-inactive material and a NERS-active
material in a radial direction. A NERS system is also disclosed that
includes a NERS-active structure. Also disclosed are methods for forming
a NERS-active structure and methods for performing NERS with NERS-active
structures.