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Published on: August 31, 2021
Momentum-Topology-Induced Optical Pulling Force
Hang Li1, Yongyin Cao1, Bojian Shi1
1Institute of Advanced Photonics, School of Physics, Harbin Institute of Technology, Harbin 150001, China.
Abstract:
We report an ingenious mechanism to obtain robust optical pulling force by a single plane wave via engineering the topology of light momentum in the background. The underlying physics is found to be the topological transition of the light momentum from a usual convex shape to a starlike concave shape in the carefully designed background, such as a photonic crystal structure. The principle and results reported here shed insightful concepts concerning optical pulling, and pave the way for a new class of advanced optical manipulation technique, with potential applications of drug delivery and cell sorting.
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