Negative nonconservative forces: optical "tractor beams" for arbitrary objects

Phys Rev Lett. 2011 Nov 11;107(20):203602. doi: 10.1103/PhysRevLett.107.203602. Epub 2011 Nov 10.


Based on the conservation of linear momentum on scattering from arbitrary objects, we demonstrate the generation of nonconservative optical forces that act in a direction opposite to the propagation of the incident beam. The concept can be applied to tailor the force fields produced on nonabsorbing bodies regardless of their sizes and shapes.