posted on 2021-12-10, 18:37authored bySeongjoon Lim, Shangke Pan, Kefeng Wang, Alexey V. Ushakov, Ekaterina V. Sukhanova, Zakhar I. Popov, Dmitry G. Kvashnin, Sergey V. Streltsov, Sang-Wook Cheong
Control
of a single ionic charge state by altering the number of
bound electrons has been considered as an ultimate testbed for atomic
charge-induced interactions and manipulations, and such subject has
been studied in artificially deposited objects on thin insulating
layers. We demonstrate that an entire layer of controllable atomic
charges on a periodic lattice can be obtained by cleaving metallic
Co1/3NbS2, an intercalated transition metal
dichalcogenide. We identified a metastable charge state of Co with
a different valence and manipulated atomic charges to form a linear
chain of the metastable charge state. Density functional theory investigation
reveals that the charge state is stable due to a modified crystal
field at the surface despite the coupling between NbS2 and
Co via a1g orbitals. The idea can be generalized to other
combinations of intercalants and base matrices, suggesting that they
can be a new platform to explore single-atom-operational 2D electronics/spintronics.