Band Engineering in Kagome Lattice on LiNbO3

We report direct, frequency-dependent imaging of surface acoustic waves (SAWs) in LiNbO3 metamaterials. Based on the analogy between the acoustic wave equation and Schrödinger equation, these metamaterials serve as a platform to rapidly prototype and characterize 2-D quantum materials. By depositing a periodic array of gold microstructures on a LiNbO3 substrate, we control SAW propagation, simulating the electronic dispersion of quantum materials with similar lattice geometry. Focusing specifically on kagome lattices, we investigate how the symmetry and arrangement of the lattice influence flat bands, dispersive bands, and band gaps. Our work demonstrates how geometry can be leveraged to tailor the propagation of SAWs for GHz technologies, such as telecommunications and signal processing. This research has been made possible with the funding provided by the Program for Research in Science and Engineering at Harvard and the Harvard Quantum Initiative.