Field-enhanced scanning optical microscope

We present experimental results of an imaging technique that uses as a loca l probe the optical field enhanced at the junction of a scanning tunneling microscope illuminated by a p-polarized laser beam. Images of highly orient ed pyrolithic graphite, recorded at a constant height mode, show a lateral optical resolution of as much as 10 nm. Approach curves exhibit sensitivity on a subnanometer scale of the optical signal to the tip-sample distance, yielding the ultrahigh vertical resolution reached in the images. (C) 2000 Optical Society of America.