▎ 摘　　要

A graphene rotational switch (GRS) is presented utilising vacancy defect and nitrogen (N) doping in armchair graphene nanoribbon (AGNR). By twisting AGNR at different angles in the suggested device, its conductivity can be controlled. Based on the simulation results it is indicated that the electronic parameters such as current, transmission, local density of state, and conductance of the suggested GRS are also associated with the width of AGNR, selection of defect or doping and its location in the AGNR. Furthermore, the results show the dependency of the proposed GRS to the voltage. In this Letter, a monotonic increase or decrease in the current between the minimum and maximum angles in the corresponding bias voltage is defined as the proper switching behaviour. The assumed defect or doping is replaced by three locations with three various widths and five different twist angles of AGNR, in different analysed modes. Devices have better switching behaviour so the range of I-max /I-min is within 37-1076 among all the modes. The best three modes are the perfects, N doping near the AGNR edge and the vacancy defect in the centre of the deformation region of AGNR in the width of 9, 10 and 11w, respectively.