Band structure engineering using a moiré polar substrate
arxiv(2024)
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 provides a unique platform for studying the
moiré structural effect without the contribution from electrostatic moiré
potentials. Tunable moiré polar substrates may serve as versatile platforms
to engineer the electronic, optical, and mechanical properties of 2D materials
and van der Waals heterostructures.
MoreTranslated text
AI Read Science
Must-Reading Tree
Example
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined