It has long been an ultimate goal to introduce chemical doping at the atomic level to precisely tune properties of materials. Two-dimensional materials have natural advantage because of its highly-exposed surface atoms, however, it is still a grand challenge to achieve this goal experimentally. Here, we demonstrate the ability to introduce chemical doping in graphene with atomic-level precision by controlling chemical adsorption of individual Se atoms, which are extracted from the underneath WSe2, at the interface of graphene-WSe2 heterostructures. Our scanning tunneling microscopy (STM) measurements, combined with first-principles calculations, reveal that individual Se atoms can chemisorbed on three possible positions in graphene, which generate distinct pseudospin-mediated atomic-scale vortices in graphene. We demonstrate that the chemisorbed positions of individual Se atoms can be manipulated by STM tip, which enables us to achieve atomic-scale controlling quantum interference of the pseudospin-mediated vortices in graphene. This result offers the promise of controlling properties of materials through chemical doping with atomic-level precision.
@article{arxiv.2311.06515,
title = {Tunable interfacial chemisorption with atomic-level precision in a graphene WSe2 heterostructure},
author = {Mo-Han Zhang and Fei Gao and Aleksander Bach Lorentzen and Ya-Ning Ren and Ruo-Han Zhang and Xiao-Feng Zhou and Rui Dong and Shi-Wu Gao and Mads Brandbyge and Lin He},
journal= {arXiv preprint arXiv:2311.06515},
year = {2023}
}