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Elastic metamaterials for independent realization of negativity in density and stiffness.

ABSTRACT: In this paper, we present the first realization of an elastic metamaterial allowing independent tuning of negative density and stiffness for elastic waves propagating along a designated direction. In electromagnetic (or acoustic) metamaterials, it is now possible to tune permittivity (bulk modulus) and permeability (density) independently. Apparently, the tuning methods seem to be directly applicable for elastic case, but no realization has yet been made due to the unique tensorial physics of elasticity that makes wave motions coupled in a peculiar way. To realize independent tunability, we developed a single-phased elastic metamaterial supported by theoretical analysis and numerical/experimental validations.

SUBMITTER: Oh JH

PROVIDER: S-EPMC4804290 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Elastic metamaterials for independent realization of negativity in density and stiffness.

Oh Joo Hwan JH Kwon Young Eui YE Lee Hyung Jin HJ Kim Yoon Young YY

Scientific reports 20160323

In this paper, we present the first realization of an elastic metamaterial allowing independent tuning of negative density and stiffness for elastic waves propagating along a designated direction. In electromagnetic (or acoustic) metamaterials, it is now possible to tune permittivity (bulk modulus) and permeability (density) independently. Apparently, the tuning methods seem to be directly applicable for elastic case, but no realization has yet been made due to the unique tensorial physics of el ...[more]

PMID: 27006310

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