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DOE OSTI · 1626006

Engineering single-atom dynamics with electron irradiation

Su, Cong·Tripathi, Mukesh·Yan, Qing-Bo·Wang, Zegao·Zhang, Zihan·Hofer, Christoph·Wang, Haozhe·Basile, Leonardo·Su, Gang·Dong, Mingdong·Meyer, Jannik C.·Kotakoski, Jani·Kong, Jing·Idrobo, Juan-Carlos·Susi, Toma·Li, Ju
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Abstract

Atomic engineering is envisioned to involve selectively inducing the desired dynamics of single atoms and combining these steps for larger-scale assemblies. Here, we focus on the first part by surveying the single-step dynamics of graphene dopants, primarily phosphorus, caused by electron irradiation both in experiment and simulation, and develop a theory for describing the probabilities of competing configurational outcomes depending on the postcollision momentum vector of the primary knock-on atom. The predicted branching ratio of configurational transformations agrees well with our atomically resolved experiments. This suggests a way for biasing the dynamics toward desired outcomes, paving the road for designing and further upscaling atomic engineering using electron irradiation.

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Su, Cong, Tripathi, Mukesh, Yan, Qing-Bo, Wang, Zegao, Zhang, Zihan, Hofer, Christoph, Wang, Haozhe, Basile, Leonardo, Su, Gang, Dong, Mingdong, Meyer, Jannik C., Kotakoski, Jani, Kong, Jing, Idrobo, Juan-Carlos, Susi, Toma, Li, Ju. 2019-05-17. Engineering single-atom dynamics with electron irradiation. https://doi.org/10.1126/sciadv.aav2252

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