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Broadband focusing and collimation of water waves by zero refractive index.

ABSTRACT: It is always a challenge to realize extreme and unusual values of refractive index for a broad range of frequencies. We show that when water is covered by a thick, rigid and unmovable plate, it behaves like a medium with zero refractive index for water waves at any frequency. Hence, by covering water with a plate of a concave or rectangular shape, water waves can be focused or collimated in a broad range of frequencies. Experiments were conducted to demonstrate these effects and results are in excellent agreement with numerical simulations.

SUBMITTER: Zhang C

PROVIDER: S-EPMC4225562 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Broadband focusing and collimation of water waves by zero refractive index.

Zhang Chi C Chan C T CT Hu Xinhua X

Scientific reports 20141110

It is always a challenge to realize extreme and unusual values of refractive index for a broad range of frequencies. We show that when water is covered by a thick, rigid and unmovable plate, it behaves like a medium with zero refractive index for water waves at any frequency. Hence, by covering water with a plate of a concave or rectangular shape, water waves can be focused or collimated in a broad range of frequencies. Experiments were conducted to demonstrate these effects and results are in e ...[more]

PMID: 25381845

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