In the last few years there has been an explosion of new quantum materials, ranging from topology to “twistronics”. Topological materials may be engineered for applications from efficient switches to spin-based computing. “Twistronics” entails the construction of layered materials with emergent electronic and magnetic properties by stacking and twisting individual 2D materials such as graphene. Despite the vast possibilities waiting to be explored, the assembly of such microscopic devices with the necessary precision has proven laborious and expensive. Here I’ll talk about my team of undergraduates working to develop tangible acoustic analogs to these tiny quantum structures! We show how sound waves propagating through millimeter-scale holes in a steel plate act exactly like electron waves propagating through nanometer-scale twisted bilayer graphene 1 . We show how to construct a topological logic gate for ultrasound 2 . Our 3D-printed acoustic structures could offer a new way to intuitively understand and rapidly preview quantum materials and devices that exceed current computational and experimental capabilities. Finally, I’ll talk about the teamwork and communication that makes this work possible.
- “Simulating twistronics in acoustic metamaterials” Gardezi et al, 2D Materials 8, 031002 (2021)
- “Topological phononic logic” Pirie et al, Phys. Rev. Lett. 128, 015501 (2022)
- https://hoffman.physics.harvard.edu/policies.html
Funding: This work was supported by the National Science Foundation Science & Technology Center for Integrated Quantum Materials, Grant No. DMR-1231319.