▎ 摘　　要

The electronic transport properties of twisted armchair graphene nanoribbons (T-AGNRs) with substitution of boron (B)/nitrogen (N) impurity as well as single vacancy (SV) are investigated using density functional theory in combination with non-equilibrium Green's function (NEGF).The results exhibit that the electronic transport properties of T-AGNRs can be clearly modulated due to the presence of B/N doping or SV. For all considered systems, the maximum variations of current are observed under twisted angle theta = 180 degrees respect to theta = 0 degrees.Thus, these systems can be considered as electromechanical switch. Furthermore, the performance of switches is investigated with B/N doping and SV in different sites of T-AGNRs. Besides, the effects of different concentrations (0.9%, 1.8%, 2.7% and 3.6%) of doping and SV are studied on overall performance of switches. The results indicate that the performance is significantly enhanced by increasing of B/N concentration. Our findings might be important to design of nano electromechanical switch devices.