Calculation of the conductance of a finite atomic line of sulfur vacancies created on a molybdenum disulfide surface

Abstract

Using the elastic-scattering quantum chemistry technique, it is shown that a surface atomic wire fabricated by extracting a line of S surface atoms from the planar $\mathrm{Mo}{\mathrm{S}}_{2}$ lamellar substrate creates enough electronic states in the $\mathrm{Mo}{\mathrm{S}}_{2}$ surface band gap for this wire to have a large conductance. The nature of the surface electronic states introduced by the S vacancies is investigated for increasing numbers of vacancies for a wire length of up to $10\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. When contacted by the two Au nanoelectrodes, the wire creates surface pseudoballistic channels and the wire conductance does not decrease with length. The effects of the nanoelectrode-wire distance and of the lateral electrode-wire overlap on the conductance of the wire are also discussed. It is found that the conductance of the junction can be increased threefold by increasing the lateral overlap.