Axicon optical forces and other kinds of transverse optical forces exerted by off-axis Bessel beams in the Rayleigh regime in the framework of generalized Lorenz-Mie theory

In two recent papers, it has been demonstrated that, beside usual scattering and optical forces, new optical forces and terms are exhibited when a Rayleigh particle is illuminated by an off-axis Bessel beam. Namely, (i) axicon optical forces are associated with scattering optical forces and (ii) additional axicon terms are associated with gradient optical forces. These extra-axicon forces and terms are zero when the axicon angle is zero and/or (most often) when an on-axis configuration is considered rather than an off-axis configuration. This study was devoted to longitudinal forces. The present paper is devoted to transverse forces and demonstrates the existence of newly additional axicon forces associated to both the usual scattering and gradient forces. Again, these new extra-axicon forces are zero when the axicon angle is zero and/or when an on-axis configuration is considered rather than an off-axis configuration. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

Two recent papers demonstrate the existence of new optical forces and terms when a Rayleigh particle is illuminated by an off-axis Bessel beam, mainly associated with the axicon angle. These forces and terms are found in both longitudinal and transverse forces studies, showing additional axicon forces linked to the usual scattering and gradient forces. These extra-axicon forces are zero when the axicon angle is zero or in an on-axis configuration rather than off-axis.