Electronic Excitations Ease Manipulation of Defects in Graphene
(top) Model phosphorous-doped armchair (left) and zigzag (right) edged graphene quantum dots overlaid with isosurfaces of the position-dependent, point-charge induced transition rate to states with low barriers for inversion. (bottom) Potential energy surfaces for inversion of the defect in these excited states (blue) and the ground state (black).
An ab initio treatment of the electronic response of materials to electron beam irradiation was developed. Transitions to defect-localized excited states of P and Si doped graphene quantum dots were predicted which present low-energy pathways for structural modifications at the defect site.
Significance and Impact
By leveraging excited state pathways, the efficiency and reliability of atomically precise dopant manipulations with focused electron beams can be optimized.
- Potential energy surface mapping revealed excited state pathways with low potential energy barriers for inversion of period 3 dopants exhibiting nonplanar equilibrium structures.
- Calculated transition probabilities suggest that these states can be accessed both optically and through electron beam exposure.
D. B. Lingerfelt, P. Ganesh, J. Jakowski, and B. G. Sumpter, "Electronically Nonadiabatic Structural Transformations Promoted by Electron Beams,"Adv. Funct. Mater.1901901 (2019). DOI:10.1002/adfm.201901901