Near-Field Optics: Light for the World of NANO

The wealth of optical phenomena offers various new opportunities for selective interaction with the world of nanometer dimensions if one succeeds in confining the optical excitation to a correspondingly small volume. Then, many optical effects manifest themselves in a novel way, having similarities with those of microwave antennas and waveguides. Scanning near-field optical microscopy (SNOM) is based on these principles. Not being limited by diffraction, SNOM readily provides a resolution of 30 to 70 nm for both amplitude and phase objects.