Making Patterned Single Defects in MoS2 Thermally with the MoS2/Au Moiré Interface

ACS Nano. 2024 Oct 8;18(40):27411-27419. doi: 10.1021/acsnano.4c07212. Epub 2024 Sep 25.

Abstract

Normally, it is hard to regulate thermal defects precisely in their host lattice due to the stochastic nature of thermal activation. Here, we demonstrate a thermal annealing way to create patterned single sulfur vacancy (VS) defects in monolayer molybdenum disulfide (MoS2) with about 2 nm separations at subnanometer accuracy. Theoretically, we reveal that the S-Au interface coupling reduces the energy barriers in forming VS defects and that explains the overwhelming formation of interface VS defects. We also discover a phonon regulation mechanism by the moiré interface that effectively condenses the Γ-point out-of-plane acoustic phonons of monolayer MoS2 to its TOP moiré sites, which has been proposed to trigger moiré-patterned thermal VS formation. The high-throughput nanoscale patterned defects presented here may contribute to building scalable defect-based quantum systems.

Keywords: MoS2; acoustic phonons; catalytic effect; moiré interface; single defects; thermal annealing.