High transmission nanoscale bowtie-shaped aperture probe for near-field optical imaging

A near-field scanning optical microscope probe integrated with nanoscale bowtie aperture for enhanced optical transmission is demonstrated. The bowtie-shape aperture allows a propagating mode in the bowtie gap region, which enables simultaneous nanoscale optical resolution and enhanced optical transmission. The optical characteristics of the bowtie aperture are demonstrated by measuring the optical near fields produced by the aperture. It is shown that bowtie aperture probes have one order of magnitude increase in transmission over probes with a regular shape aperture of the same resolution. The imaging results using bowtie aperture are in agreement with those obtained from numerical calculations.