Development of Tip-Enhanced Near-Field Optical Spectroscopy and Microscopy

Abstract

Near-field scanning optical microscopy has been developed as a combination of scanning probe microscopy and optical microscopy in which the spatial resolution is determined by scanning probe microscope resolution while the signals detected are coming from several optical interactions. As a result, near-field scanning optical microscopy has achieved higher spatial resolution than that of the classical optical microscopy that uses a conventional lens, which is strictly limited by the diffraction limit of light. In this paper, recent advances in near-field optical microscopy and spectroscopy are reviewed, particularly, the metal tip based probes. The discussion covers tip-enhancement effect in various wavelength regions, deep ultraviolet (DUV), ultraviolet (UV), visible (vis), and infrared (IR) up to terahertz (THz) frequency.