Valley Anisotropy in Elastic Metamaterials
| Autor: | Satoshi Iwamoto, Jianfeng Zang, Ingi Kim, Shuaifeng Li, Jinkyu Yang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Physics
Condensed Matter - Materials Science Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences Metamaterial Physics::Optics Applied Physics (physics.app-ph) 02 engineering and technology Physics - Applied Physics Type (model theory) 021001 nanoscience & nanotechnology Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 01 natural sciences Theoretical physics Symmetric systems Topological insulator 0103 physical sciences Valleytronics Berry connection and curvature 010306 general physics 0210 nano-technology Anisotropy Topology (chemistry) Physics::Atmospheric and Oceanic Physics |
| Popis: | Valley, as a new degree of freedom, raises the valleytronics in fundamental and applied science. The elastic analogs of valley states have been proposed by mimicking the symmetrical structure of either two-dimensional materials or photonic valley crystals. However, the asymmetrical valley construction remains unfulfilled. Here, we present the valley anisotropy by introducing asymmetrical design into elastic metamaterials. The elastic valley metamaterials are composed of bio-inspired hard spirals and soft materials. The anisotropic topological nature of valley is verified by asymmetrical distribution of the Berry curvature. We show the high tunability of the Berry curvature both in magnitude and sign enabled by our anisotropic valley metamaterials. Finally, we demonstrate the creation of valley topological insulators and show topologically protected propagation of transverse elastic waves relying on operating frequency. The proposed topological properties of elastic valley metamaterials pave the way to better understanding the valley topology and to creating a new type of topological insulators enabled by an additional valley degree of freedom. 22 pages, 7 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|