The size-dependent magnetoconductance of a polyacetylene nanoring

In this paper, we study the size-dependent electronic conductance of a polyacetylene nanoring in the presence and absence of magnetic field by using Green’s function technique at the tight-binding approach. We consider two types of the nanoring that the number of single and double bonds in the possible paths for electron be or not be identical. The results show that the tunneling conductance in the gap region decreases exponentially and the number of peaks in the resonance region increases by increasing the length of the nanoring. By applying a magnetic field, the position of resonance peaks in the conductance spectrum shift and the tunneling conductance changes too. This means that for a nanoring with fixed length and in the presence of magnetic field, the tunneling conductance improves for the case that there is not bonding symmetry on the electron paths with respect to the absence of field. There is a vise-versa situation for the symmetric case.