Showing 2 results for Tight-Binding
Hassan Rabani, Azadeh Mazloom Shahraki,
Volume 12, Issue 4 (11-2013)
Abstract
In this paper, we studied the electronic conductance and energy gap of a graphene nano-ribbon which is connected to two semi-infinite atomic chains by the atoms located in the opposite sides of nano-ribbon. The numerical calculations were performed using the Green’s function method in the nearest neighbor approximation of tight-binding approach. The conductance curves plotted with respect to incoming electron energy show that for a zigzag graphene nano-ribbon with one benzene ring in its width, there is no gap in the energy band spectra of the system, while for the armchair case, an energy gap always exists around the Fermi energy and its value depends on the size of the nano-ribbon. The results show that the behavior of the graphene nano-ribbons conductance strongly depends on that how and where the leads connect to the nano-ribbon and on the contacts qualities.
Hassan Rabani, Mohammad Mardaani, Hamideh Vahid,
Volume 14, Issue 2 (7-2014)
Abstract
In this paper, we study the electronic transport of a multi-molecular chain of copper phthalocyanine connected to two metallic leads by using Green’s function method at the tight-binding approach. The results show that in the gaps of this system, the density of states is independent of the number of molecules or the system length. Moreover, increasing of the system length decreases the tunneling conductance and causes the appearance of peaks and dips in the gaps of the conductance spectra and depending on the value of incoming electron energy, the electron tunneling takes place easier, especially in the edges of the gaps.