Pulling and spinning reversal of a subwavelength absorptive sphere in adjustable vector Airy light-sheets

• Published in: Applied physics letters Vol. 110; no. 18
• Main Author: Mitri, F. G.
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 01-05-2017
• Subjects: Absorptivity; Applied physics; Axial stress; Electric dipoles; Light sheets; Maxwell's equations
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4982784

In the framework of the electric dipole approximation, this work demonstrates the generation of a pulling/attractive longitudinal force and an axial spin torque sign reversal causing counterclockwise or clockwise rotation of a subwavelength absorptive sphere placed in adjustable Airy light-sheets. Based on the vector angular spectrum decomposition method, the Lorenz gauge condition and Maxwell's equations, the Cartesian components of the incident radiated electric field of the generalized adjustable solution are derived, for which the main maximum Airy-lobe (i.e. caustic) is translated in space. The results find potential applications in the design/manufacture of particle manipulation and optical sorting devices using adjustable Airy-light sheets.