It is known that core–shell subwavelength nanoparticles consisting of a dielectric shell and a metallic core can simultaneously support electric and magnetic dipolar resonances, which enhance forward scattering and suppress backward scattering. This creates favorable conditions for optical tractor beam applications. Using the generalized Lorenz–Mie theory and Maxwell stress tensor formulation, we demonstrate how optical pulling forces can be induced and optimized by first-order Bessel beams with appropriate polarization. The transverse stability of the core–shell nanoparticle under ambient damping is also verified by linear stability analysis and dynamical simulation.
© 2014 Optical Society of America
Original Manuscript: December 23, 2013
Revised Manuscript: March 3, 2014
Manuscript Accepted: March 18, 2014
Published: April 9, 2014
Vol. 9, Iss. 6 Virtual Journal for Biomedical Optics
Neng Wang, Wanli Lu, Jack Ng, and Zhifang Lin, "Optimized optical “tractor beam” for core–shell nanoparticles," Opt. Lett. 39, 2399-2402 (2014)