Light capsules shaped by curvilinear meta-surfaces

TL;DR

This paper introduces a novel method for generating in-plane hollow optical beams with circular light shells using phase modulation of near-field wavefronts and engineered plasmonic meta-surfaces, enabling optical trapping and beam shaping.

Contribution

It presents a new approach combining phase modulation and plasmonic nanoslits to create circular caustic surfaces for optical trapping applications.

Findings

Successfully generates nearly-full circular light shells

Demonstrates beam acceleration using engineered plasmonic meta-surfaces

Numerically shows creation of optical bottle with circular caustic surface

Abstract

We propose a simple yet efficient method for generating in-plane hollow beams with a nearly-full circular light shell without the contribution of backward propagating waves. The method relies on modulating the phase in the near field of a centro-symmetric optical wavefront, such as that from a high-numericalaperture focused wave field. We illustrate how beam acceleration may be carried out by using an ultranarrow non-flat meta-surface formed by engineered plasmonic nanoslits. A mirrorsymmetric, with respect to the optical axis, circular caustic surface is numerically demonstrated that can be used as an optical bottle.