Optical forces from an evanescent wave on a magnetodielectric small particle

TL;DR

This paper investigates how evanescent waves exert optical forces on small magnetodielectric particles, revealing new effects from electric and magnetic dipoles and their interactions, with force behavior depending on medium, polarization, and surface wave characteristics.

Contribution

It provides the first analysis of optical forces on magnetodielectric particles from evanescent waves, including new expressions and effects involving electric and magnetic dipoles and their interactions.

Findings

Force depends on medium, polarization, and surface wave properties.

New expressions for gradient, radiation pressure, and curl components.

Potential for dramatic force changes based on particle and wave parameters.

Abstract

We report the first study on the optical force exerted by an evanescent wave on a small sphere with both electric and magnetic response to the incident field, immersed in an arbitrary nondissipative medium. New expressions and effects from their gradient, radiation pressure, and curl components are obtained due to the particle induced electric and magnetic dipoles, as well as to their mutual interaction. We predict possible dramatic changes in the force depending on either the host medium, the polarization and the nature of the surface wave.