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arXiv · 2111.09149

Gate-tunable artificial nucleus in graphene

Mykola Telychko·Keian Noori·Hillol Biswas·Dikshant Dulal·Pin Lyu·Jing Li·Hsin-Zon Tsai·Hanyan Fang·Zhizhan Qiu·Zhun Wai Yap·Kenji Watanabe·Takashi Taniguchi·Michael F. Crommie·Aleksandr Rodin·Jiong Lu
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Abstract

We report an atomically-precise integration of individual nitrogen (N) dopant as an in-plane artificial nucleus in a graphene device by atomic implantation to probe its gate-tunable quantum states and correlation effects. The N dopant creates the characteristic resonance state in the conduction band, revealing a giant carrier-dependent energetic renormalization up to 350 meV with respect to the Dirac point, accompanied by the observation of long-range screening effects. 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.

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Mykola Telychko, Keian Noori, Hillol Biswas, Dikshant Dulal, Pin Lyu, Jing Li, Hsin-Zon Tsai, Hanyan Fang, Zhizhan Qiu, Zhun Wai Yap, Kenji Watanabe, Takashi Taniguchi, Michael F. Crommie, Aleksandr Rodin, Jiong Lu. 2021-11-17. Gate-tunable artificial nucleus in graphene. https://arxiv.org/abs/2111.09149

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