Acoustic Moiré Flat Bands in Twisted Heterobilayer Metasurface

Twisted bilayer systems enable a fundamental platform for engineering novel physical phenomena, such as topological phase transitions, polaritons, flat bands, and superconductivity. However, previous reports mainly focused on homobilayer structures, where each layer has identical configurations. In this work, a twisted heterobilayer (tHB) metasurface with strong anisotropy is presented. It is shown that hybridizing the dispersion curves of two different profiles significantly enhances the application potential of bilayer structures. It is observed that when two stacked heterogeneous metasurfaces are rotated to a specific angle, a topological phase transition occurs, which is accompanied by hyperbolic to…

• RU
  Rowan University
• NN
  National Natural Science Foundation of China

  Awards: 12072221, 52475114, 12232014
• HI
  Harbin Institute of Technology
• NK
  National Key Research and Development Program of China

  Award: 2023YFB3408502
• FR
  Fundamental Research Funds for the Central Universities

  Award: N2403027
• NT
  National Ten Thousand Talent Program