Nanometric probe-sample interactions via optical near fields: derivation and characteristics

Summary form only given. Recent experimental studies have revealed distinct characteristics of optical near fields. Highly localized optical near fields could be applied to not only a high-resolution microscope beyond the diffraction limit of light but also fabrication of nanometric devices. From this point of view, a theory, which quantitatively deals with interactions between a nanometric probe tip and sample, is required to describe the optical near-field systems. We have proposed a microscopic formulation of the optical near-field systems, and found that elementary excitation modes of exciton-polaritons, or virtual photons, give a good explanation for general properties of optical near fields. In this report, we derive the effective interactions more rigorously and elucidate characteristics of a nanometric probe-sample system.