Near-field optical control of doughnut-shaped nanostructures

Abstract

The application of a local near-field optical excitation can be used to control step-by-step the reshape of individual doughnut-shaped azopolymer nano-objects by varying the time of illumination demonstrating its promising performance as a functional nano-object. The possibility to provide both photoinduced reshaping opens a way to the fundamental study of size-dependent scaling laws of optical properties, photoinduced reshaping efficiency and nanoreactor or nanoresonator behavior at nanometer scale. As an example the nano-object is used to self-assembly polystyrene nanospheres in a supraball.

Photonic applications of azobenzene molecules embedded in amorphous polymer

“…If azomaterials properties are coupled with other fabrication techniques, micro/nano structures of different shape and size can be realized [11,134,135] e.g. parallel groves [32,107,112,136], array of microporous [137][138][139][140][141] and hemispherical caps [142,143], whose geometry can be successively modified. Indeed, this technique allows to produce very sophisticated micro/nanoarchitecture that would be difficult to attain with other methods [12,107,144,145].…”

A new method for patterning azopolymer thin film surfaces

“…This light induced movement has been recognized as a useful tool to enforce reversible changes in a variety of molecular systems; a possible technology for a broad range of fundamental and applied researches [4]. The mass transport not only provides a unique opportunity for nanostructure formation but also due to the unique photophysical behavior of these materials, azopolymers nanostructures can be optimized and reshaped via controlled light field, to gain the desired behavior [5].…”