Three-dimensional acoustic sub-diffraction focusing by coiled metamaterials with strong absorption
发布时间：2025-04-30
点击次数：
- 发布时间：
- 2025-04-30
- 论文名称：
- Three-dimensional acoustic sub-diffraction focusing by coiled metamaterials with strong absorption
- 发表刊物：
- Journal of Materials Chemistry C
- 摘要：
- The diffraction limit restricts the smallest diameter of a wave’s focal spot in a homogeneous medium to no less than half of the operating wavelength. The diffraction limit originates from the interference between converging and diverging waves, however, in this paper, a focus spot beyond the diffraction limit is realized by employing a point-like sink at the focus point to change this interference, thereby eliminating or reducing the diverging waves, using subwavelength coiled acoustic metamaterial absorbers. This sub-diffraction focusing effect is intuitively demonstrated in a number of three-dimensional timereversal acoustic experiments, for which a planar coiled structure and two types of hemispherical coiled structures were respectively designed. Here, these linear, planar and spherical sub-diffraction focusing results are detailed and the corresponding physical mechanisms are discussed.
- 合写作者：
- Fuyin Ma, Jianyu Chen, Jiu Hui Wu
- 卷号：
- 7
- 页面范围：
- 5131-5138
- 是否译文：
- 否
- 发表时间：
- 2019-04-11