Controlling Rotation of 2D Material Flakes

ACS Nano (2019), in press (https://pubs.acs.org/doi/10.1021/acsnano.9b01794).

Shuze Zhu, Pascal Pochet, and Harley T. Johnson

Abstract: Interlayer rotational alignment in vdW structures of two-dimensional materials couples strongly to electronic properties and, therefore, has significant technological implications. Nevertheless, controlling rotation of an arbitrary two-dimensional material flake remains a challenge in the development of rotation-tunable electronics, for the emerging field of twistronics. In this Letter, we reveal a general moiré-driven mechanism that governs the interlayer rotation. Controlling the moiré can therefore hold promise for controlling interlayer rotation. We further demonstrate mismatch strain engineering as a useful tool to design the interlayer rotation via changing the energy landscape of moiré within a finite-sized region. The robustness and programmable nature of our approach arise from moiré symmetry, energetics, and mechanics. Our approach provides another possibilities to the on-demand design of rotation-tunable electronics.