Electrolytic formation of nanoapertures for scanning near-field optical microscopy

Abstract
Aperture probes for near-field optical microscopy were produced by controlled all solid state electrolysis. Control of both the ionic current and light transmission provided reproducible probe tips with aperture diameters in the sub-50 nm range and flat end faces. High resolution scanning near-field optical microscopy images were obtained with these probes. As a by-product, the formation of an electrolytic nanometer-sized contact was observed.