Optical Near-Field Probe With Embedded Gallium Scattering Center

An optical near-field probe is proposed in which gallium is embedded into the tip of a tapered optical glass fiber to form a scattering center. Gallium is embedded by implantation during the process of probe sharpening by a raster-scanned focused ion beam. Using quasielectrostatic approximation, it is predicted that the presence of gallium should improve the scattering efficiency by an order of magnitude in comparison with a probe without gallium implantation. Imaging of a polished waveguide with different probes shows that Ga implantation can improve the efficiency by 37 times.