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Experimental demonstration of angular momentum-dependent topological transport using a transmission line network.

ABSTRACT: Novel classical wave phenomenon analogs of the quantum spin Hall effect are mostly based on the construction of pseudo-spins. Here we show that the non-trivial topology of a system can also be realized using orbital angular momentum through a coupling between the angular momentum and the wave vector. The idea is illustrated with a tight-binding model and experimentally demonstrated with a transmission line network. We show experimentally that even a very small network cluster exhibits angular momentum-dependent one-way topological edge states, and their properties can be described in terms of local Chern numbers. Our work provides a new mechanism to realize counterparts of the quantum spin Hall effect in classical waves and may offer insights for other systems.

SUBMITTER: Jiang T

PROVIDER: S-EPMC6347663 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Experimental demonstration of angular momentum-dependent topological transport using a transmission line network.

Jiang Tianshu T Xiao Meng M Chen Wen-Jie WJ Yang Lechen L Fang Yawen Y Tam Wing Yim WY Chan C T CT

Nature communications 20190125 1

Novel classical wave phenomenon analogs of the quantum spin Hall effect are mostly based on the construction of pseudo-spins. Here we show that the non-trivial topology of a system can also be realized using orbital angular momentum through a coupling between the angular momentum and the wave vector. The idea is illustrated with a tight-binding model and experimentally demonstrated with a transmission line network. We show experimentally that even a very small network cluster exhibits angular mo ...[more]

PMID: 30683898

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