Switchable optical forces due to polarization-dependent spin-orbit coupling on particles near a surface

Spin-orbit coupling enables highly directional scattering of light from a particle by controlling the incident polarization. We propose using polarized illumination to induce lateral scattering, associated with a lateral electromagnetic momentum, and therefore accompanied by an unusual recoil force (equal and opposite mechanical momentum) that can be switched with the polarization, with no field gradients, and perpendicular to the illumination.