Gate-Tunable Resonance State and Screening Effects for Proton-Like Atomic Charge in Graphene
Mykola Telychko, Keian Noori, Hillol Biswas, Dikshant Dulal, Zhaolong Chen, Pin Lyu, Jing Li, Hsin‐Zon Tsai, Hanyan Fang, Zhizhan Qiu, Zhun Wai Yap, Kenji Watanabe, Takashi Taniguchi, Jing Wu, Kian Ping Loh, Michael F. Crommie, Aleksandr Rodin, Jiong Lu
Abstract
The ability to create a robust and well-defined artificial atomic charge in graphene and understand its carrier-dependent electronic properties represents an important goal toward the development of graphene-based quantum devices. Herein, we devise a new pathway toward the atomically precise embodiment of point charges into a graphene lattice by posterior (N) ion implantation into a back-gated graphene device. The N dopant behaves as an in-plane proton-like charge manifested by formation of the characteristic resonance state in the conduction band. Scanning tunneling spectroscopy measurements at varied charge carrier densities reveal a giant energetic renormalization of the resonance state up to 220 meV with respect to the Dirac point, accompanied by the observation of gate-tunable long-range screening effects close to individual N dopants. Joint density functional theory and tight-binding calculations with modified perturbation potential corroborate experimental findings and highlight the short-range character of N-induced perturbation.