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Topology in momentum space becomes real

Using topological singular points, the topological charge of photonic crystals in momentum space is successfully transferred to optical vortex beams in real space.

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Fig. 1: Generation of an optical vortex with ei2θ by a photonic crystal.


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Correspondence to Masaya Notomi.

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Notomi, M. Topology in momentum space becomes real. Nat. Photonics 14, 595–596 (2020).

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