Abstract
Applying long wavelength periodic potentials on quantum materials has recently been demonstrated to be a promising pathway for engineering novel quantum phases of matter. Here, we utilize twisted bilayer boron nitride (BN) as a moiré substrate for band structure engineering. Small-angle-twisted bilayer BN is endowed with periodically arranged up and down polar domains, which imprints a periodic electrostatic potential on a target two-dimensional (2D) material placed on top. As a proof of concept, we use Bernal bilayer graphene as the target material. The resulting modulation of the band structure appears as superlattice resistance peaks, tunable by varying the twist angle, and Hofstadter butterfly physics under a magnetic field. Additionally, we demonstrate the tunability of the moiré potential by altering the dielectric thickness underneath the twisted BN. Finally, we find that near-60°-twisted bilayer BN also leads to moiré band features in bilayer graphene, which may come from the in-plane piezoelectric effect or out-of-plane corrugation effect. Tunable twisted BN substrate may serve as versatile platforms to engineer the electronic, optical, and mechanical properties of 2D materials and van der Waals heterostructures.
| Original language | English |
|---|---|
| Article number | 178 |
| Journal | Nature Communications |
| Volume | 16 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2025 |
Funding
We thank A. Reddy for help in fabrication, and J. Cano, S.A.A. Ghorashi, M. Koshino, and V.I. Fal’ko for fruitful discussions. This research was supported by the Center for the Advancement of Topological Semimetals, an Energy Frontier Research Center funded by the U.S. Department of Energy Office of Science, through the Ames Laboratory under contract DE-AC02-07CH11358 (measurements and data analysis), the MIT/Microsystems Technology Laboratories Samsung Semiconductor Research Fund, the Gordon and Betty Moore Foundation’s EPiQS Initiative through grant GBMF9463, and the Ramon Areces Foundation. This work was performed in part at the Harvard University Center for Nanoscale Systems (CNS), a member of the National Nanotechnology Coordinated Infrastructure Network (NNCI), which is supported by the National Science Foundation under NSF ECCS award No. 1541959. This work was carried out in part through the use of MIT.nano’s facilities. C.X. and Y.Z. are supported by the start-up fund at University of Tennessee Knoxville, and the Max Planck Partner lab on quantum materials from Max Planck Institute Chemical Physics of Solids. S.A. is partially supported by the NSF Graduate Research Fellowship Program via grant no. 1122374. D.B. and E.K. acknowledge the US Army Research Office (ARO) MURI project under grant No. W911NF-21-0147 and from the Simons Foundation award No. 896626. N.P. acknowledges the Kavli Institute for Theoretical Physics (KITP) graduate fellowship. K.W. and T.T. acknowledge support from the JSPS KAKENHI (Grant Numbers 21H05233 and 23H02052) and World Premier International Research Center Initiative (WPI), MEXT, Japan.