Here, the authors report phonon transmission through a nonlocal material slab embedded in a local material and perform an analysis based on a one-dimensional mass-and-spring model. Evidence of rich phonon behaviours, including sharp resonances related to bound-states-in-the-continuum, are found and reproduced by a developed higher-order-gradient effective medium theory for nonlocal materials.
- Yi Chen
- Ke Wang
- Martin Wegener