Breaking the diffraction barrier - Optical microscopy on a nanometric scale

In near-field scanning optical microscopy, a light source or detector with dimensions less than the wavelength (lambda) is placed in close proximity (below lambda/50) to a sample to generate images with resolution better than the diffraction limit. A near-field probe has been developed that yields a resolution of about 12 nm (about lambda/43) and signals about 10,000- to one million-fold larger than those reported previously. In addition, image contrast is demonstrated to be highly polarization dependent. With these probes, near-field microscopy appears poised to fulfill its promise by combining the power of optical characterization methods with nanometric spatial resolution.