120
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Ultrasonic metamaterials with negative modulus.

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          The emergence of artificially designed subwavelength electromagnetic materials, denoted metamaterials, has significantly broadened the range of material responses found in nature. However, the acoustic analogue to electromagnetic metamaterials has, so far, not been investigated. We report a new class of ultrasonic metamaterials consisting of an array of subwavelength Helmholtz resonators with designed acoustic inductance and capacitance. These materials have an effective dynamic modulus with negative values near the resonance frequency. As a result, these ultrasonic metamaterials can convey acoustic waves with a group velocity antiparallel to phase velocity, as observed experimentally. On the basis of homogenized-media theory, we calculated the dispersion and transmission, which agrees well with experiments near 30 kHz. As the negative dynamic modulus leads to a richness of surface states with very large wavevectors, this new class of acoustic metamaterials may offer interesting applications, such as acoustic negative refraction and superlensing below the diffraction limit.

          Related collections

          Author and article information

          Journal
          Nat Mater
          Nature materials
          Springer Science and Business Media LLC
          1476-1122
          1476-1122
          Jun 2006
          : 5
          : 6
          Affiliations
          [1 ] Nano-scale Science and Engineering Center, 5130 Etcheverry Hall, University of California, Berkeley, California 94720-1740, USA.
          Article
          nmat1644
          10.1038/nmat1644
          16648856
          b60e38c4-0656-4350-9faa-ecfde2d2b8a6
          History

          Comments

          Comment on this article