Proposed scheme of realization of artificial nano-heterostructures by optical force under double resonance

Abstract

We theoretically study a new configuration control of nanoparticles based on an optical force, which enables to trap two kinds of nanoparticles simultaneously in two-dimensional hetero-arrangement. Our proposed scheme utilizes two resonance effects on a localized surface plasmon and an electronic transition of nanoparticles. These resonances change the optical force behavior significantly. We propose periodic rhomboid metallic nanostructures with two linear polarized laser beams, the directions of which polarization are parallel to the two diagonals of rhomboid. The polarization direction fractionates the trapped nanoparticles when the two laser frequencies correspond to the electronic transition energies of two kinds of particles, respectively. We evaluate the feasibility of our proposed scheme numerically. The map of the optical force shows a clear spatial separation of trapping position for the two kinds of particles. Our results demonstrate an essential advantage of the optical manipulation that enables creating novel nanostructures unrealizable by conventional nanofabrication techniques.