Publications [#348644] of Joshua Socolar
- Tian, Z; Shen, C; Li, J; Reit, E; Bachman, H; Socolar, J; Cummer, S; Huang, T, Dispersion Tuning and Route Reconfiguration of Acoustic Waves in Valley Topological Phononic Crystals,
Nature Communications, vol. 11 no. 1
pp. 762 (J.E.S.S consulted on the interpretation of experimental results, suggested additional studies needed for clarifying key features, and made substantial contributions to the preparation of the manuscript. The primary faculty supervisors of the project were MEMS professors S. A. Cummer and T. J. Huang.) [doi]
[high impact paper]
(last updated on 2021/12/02)
This paper describes a patterned mechanical system (a "phononic crystal") that allows for the tuning of dispersion relations and energy propagation paths of acoustic waves in a quasi-2D layer of air. The system allows for the realization of multiple functionalities based on topologically protected features such as edge states at interfaces. Experimental and numerical studies demonstrate a significant advance in the engineering phononic crystals for multiple purposes.
The valley degree of freedom in crystals offers great potential for manipulating classical waves; however, few studies have investigated valley states with complex wavenumbers, valley states in graded systems, or dispersion tuning for valley states. Here, we present tunable valley phononic crystals (PCs) composed of hybrid channel-cavity cells with three tunable parameters. Our PCs support valley states and Dirac cones with complex wavenumbers. They can be configured to form chirped valley PCs in which edge modes are slowed to zero group velocity states, where the energy at different frequencies accumulates at different designated locations. They enable multiple novel functionalities, including tuning of dispersion relations for valley states, robust routing of surface acoustic waves, and spatial modulation of group velocities. This work may spark future investigations of topological states with complex wavenumbers in other classical systems, further study of topological states in graded materials, and the development of novel acoustic devices.