Observation of Optical Near-Field as Photo-Induced Surface Relief Formation

Abstract

The spatial distribution and the polarization condition of the optical near-field has successfully been visualized for the first time. It is realized in connection with the photo-induced surface relief formation on the azobenzene functionalized polymer film that had been reported so far only on the optical far-field condition. In this study, the observation was performed for linear and circular polarized light irradiation. The proposed technique is considered to be as a simple and an effective method to analyze the optical near-field.

Azopolymer‐based micro‐ and nanopatterning for photonic applications

“…In context of near‐field optics, azopolymers have been used to visualize the optical‐field distributions at the vicinity of probe tips of near‐field optical microscopes, and to map the optical response of surface‐mounted copper nanoislands . As an example, Figure (a,b) display the surface deformation of an initially flat film irradiated through a metal‐coated tapered optical fiber .…”

Optical and Physical Applications of Photocontrollable Materials: Azobenzene-Containing and Liquid Crystalline Polymers

“…Ikawa and coworkers proposed a method using polystyrene nanospheres and suggested that the spatial resolution obtained by the method is at least 20 nm [122]. Boilot and coworkers and Fukuda and coworkers independently demonstrated that the formation of a nanoscale dot array and nano-characters was possible by a method using an optical fiber with a tiny aperture at the tip [123][124][125]. Sekkat and coworkers reported a silver-coated tip for an atomic force microscope that can generate an optical near-field spot, and can be used for near-field nanofabrication [126].…”

Nano‐fabrication of azopolymer by scanning near‐field optical microscope

“…Due to these characteristics, it is possible to produce highly sensitive deformation by near-field light generated by an infinitesimal sphere [6,7], inducement of birefringence caused by orientation of the chromophores due to illumination with linearly polarized light [8], and formation of a surface relief grating according to an exposure pattern by two-optical-flux interference exposure [9]. There have been several studies of nanofabrication with azopolymer by near-field light illumination from a probe [10,11]. However, from the point of view of optical nanofabrication using near-field light, additional detailed data are needed on the surface deformation when the probe tip light intensity, illumination time, polarization condition, probe aperture diameter, and probe-material distance are varied.…”