Abstract

Deep subwavelength integration of high-definition plasmonic nanostructures is of key importance for the development of future optical nanocircuitry for high-speed communication, quantum computation, and lab-on-a-chip applications. So far the experimental realization of extended plasmonic networks consisting of multiple functional elements remains challenging, mainly due to the multi-crystallinity of commonly used thermally evaporated gold layers. Resulting structural imperfections in individual circuit elements will drastically reduce the yield of functional integrated nanocircuits. Here we demonstrate the use of very large (>100 μm²) but thin (<80 nm) chemically grown single-crystalline gold flakes (see Fig. 1), which, after immobilization, serve as an ideal basis for focused-ion beam milling and other top-down nanofabrication techniques on any desired substrate. Using this methodology we obtain high-definition ultrasmooth gold nanostructures with superior optical properties [1] and reproducible nano-sized features [2] over micrometer length scales. Our approach overcomes the current fabrication bottleneck and opens the road for the realization of extended plasmonic circuitry.

© 2011 Optical Society of America