Electronic Transmission Wave Function of Disordered Graphene by Direct Method and Green's Function Method
الموضوعات : فصلنامه نانوساختارهای اپتوالکترونیکی
1 - Department of physics, Faculty of science, Imam Khomeini International University, Qazvin, Iran
الکلمات المفتاحية: Finite difference method, Graphene, Disordered graphene, Green's function,
ملخص المقالة :
We describe how to obtain electronic transport properties of disordered graphene, including the tight binding model and nearest neighbor hopping. We present a new method for computing, electronic transport wave function and Greens function of the disordered Graphene. In this method, based on the small rectangular approximation, break up the potential barriers in to small parts. Then using the finite difference method, the Dirac equations of disordered graphene, reduce to the discrete matrix equation. The discrete matrix equation is solved by direct and Green’s function methods. In this method, geometry of disorder plays an important role. This method allows for an amenable inclusion of several disorder mechanisms at the microscopic level. The effect of impurity on the transmission probability and conductivity are obtained, using the electronic transport wave function. The results show that, for the conductance, geometry plays an important role. In addition, by transmission probability and using Landau formula, the Fano factor is investigated.
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