Three-dimensional columnar optical nanostructures fabricated by using lithography-free templating approach.

Using a nanowire-based templating approach, lithography-free fabrication of three-dimensional circular optical nanostructures with a minimum physical size of 20 nm is demonstrated. Regular circular gratings with alternating transparent and opaque annular zones and having discrete nanometer length scale separations can be easily achieved. These columnar optical nanostructures could potentially be used for direct integration with other optical components. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]