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Asymmetric topological pumping in nonparaxial photonics.

ABSTRACT: Topological photonics was initially inspired by the quantum-optical analogy between the Schrödinger equation for an electron wavefunction and the paraxial equation for a light beam. Here, we reveal an unexpected phenomenon in topological pumping observed in arrays of nonparaxial optical waveguides where the quantum-optical analogy becomes invalid. We predict theoretically and demonstrate experimentally an asymmetric topological pumping when the injected field transfers from one side of the waveguide array to the other side whereas the reverse process is unexpectedly forbidden. Our finding could open an avenue for exploring topological photonics that enables nontrivial topological phenomena and designs in photonics driven by nonparaxiality.

SUBMITTER: Cheng Q

PROVIDER: S-EPMC8752818 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Asymmetric topological pumping in nonparaxial photonics.

Cheng Qingqing Q Wang Huaiqiang H Ke Yongguan Y Chen Tao T Yu Ye Y Kivshar Yuri S YS Lee Chaohong C Pan Yiming Y

Nature communications 20220111 1

Topological photonics was initially inspired by the quantum-optical analogy between the Schrödinger equation for an electron wavefunction and the paraxial equation for a light beam. Here, we reveal an unexpected phenomenon in topological pumping observed in arrays of nonparaxial optical waveguides where the quantum-optical analogy becomes invalid. We predict theoretically and demonstrate experimentally an asymmetric topological pumping when the injected field transfers from one side of the waveg ...[more]

PMID: 35017483

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