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Optical forces arising from phase gradients

Yohai Roichman·Bo Sun·Yael Roichman·Jesse Amato-Grill·David G. Grier
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Abstract

We demonstrate both theoretically and experimentally that gradients in the phase of a light field exert forces on illuminated objects, including forces transverse to the direction of propagation. This effect generalizes the notion of the photon orbital angular momentum carried by helical beams of light. We further demonstrate that these forces generally violate conservation of energy, and briefly discuss some ramifications of their non-conservativity.

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Yohai Roichman, Bo Sun, Yael Roichman, Jesse Amato-Grill, David G. Grier. 2007-03-21. Optical forces arising from phase gradients. https://doi.org/10.1103/physrevlett.100.013602

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