Manipulating elastic waves in lower-dimensional mechanical metamaterials has attracted much attention since it lays the foundations for the design of various elastic functional devices, especially for on-chip size. However, due to the experimental challenges, it is very difficult to control elastic waves in higher dimensions, which thus limit their further applications. In this paper, we introduce an extra structural parameter to synthesize and investigate the on-chip Weyl physics in silicon-on-insulator system. Interestingly, we engineer an in-plane pseudomagnetic field to realize chiral Landau levels, which provides a bulk channel supporting robust energy transport. We also observe the pseudomagnetic field-induced boundary states near the diagonal corners, which are quite different from conventional higher order topological corner states. With the aid of synthetic dimension, we can not only realize the multidimensional elastic wave manipulations, but more importantly, devise a novel strategy to explore the higher dimensional physics on an integrated platform.

Dr. Mou Yan received his Ph.D. degree from South China University of Technology in 2019, and conducted postdoctoral research from 2019 to 2022. After which he joined the School of Physics and Laboratory of Zhongyuan Light, Zhengzhou University. His research focuses on acoustic metamaterials and topological physics, particularly topological transport phenomena in elastic wave systems. He has published more than 30 SCI papers, with 20 papers as first/corresponding author. His research findings have been selected as the cover and Editor's Suggestion of Physical Review Letters. He has led two General Projects funded by the National Natural Science Foundation of China, and has acquired the National Postdoctoral Innovative Talents Support Program.