Calculation of electronic structures of WS2 armchair nanoribbons doped with transition metals.

Yan-Hong Chen¹, Chi-Hsuan Lee², Shun-Jen Cheng¹, Chih-Kai Yang^2*

¹Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan
²Graduate Institute of Applied Physics, National Chengchi University, Taipei, Taiwan

* Presenter:Chih-Kai Yang, email:ckyang@nccu.edu.tw

Armchair WS2 nanoribbons are semiconductors with band gaps close to 0.5 eV. When a W atom is replaced by a transition metal, impurity states can have tremendous effects on the overall electronic structures. By using first-principles calculations based on density functional theory, we investigated substitutional doping of Ti, V, Cr, Mn, Fe, Co for WS2 ribbons of different widths. We found that Fe-doped ribbons can have two-channel conduction separately in the middle part of the ribbon and at the edges. Co-doped ribbons are turned in to spin filters, having 100% spin-polarized conductions. These results should be useful for nano-electronic circuit design.

Keywords: WS2 nanoribbons, Substitutional doping, Two-channel conduction, Spin filter, DFT calculation