Near-field scanning optical microscopy with an active probe

Abstract

A near-field scanning optical microscopy (NSOM) system employing a very-small-aperture laser (VSAL) as an active probe is reported in this Letter. The VSAL in our experiment has an aperture size of 300nm×300nm and a near-field spot size of about 600nm. The resolution of the NSOM system with the VSAL can reach about 600nm, and even 400nm. Considering the high output power of the VSAL, such a NSOM system is a potentially useful tool for nanodetection, data storage, nanolithography, and nanobiology.