Nanomovement of azo polymers induced by metal tip enhanced near-field irradiation

Abstract

Nanomovement of azo polymers induced by metal tip enhanced near-field illumination was studied. A protrusion with 47nm full width at half maximum was induced with a resolution beyond the diffraction limit. At the top of the protrusion, an anisotropic movement occurs in a direction nearly parallel to the polarization of the incident light, and suggests the existence at the tip end of not only a longitudinal but also a lateral component of the electric field of light. The anisotropic photofluidity and the optical gradient force played important roles in the process of the light induced polymer movement.