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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Improved recursive Green's function formalism for quasi onedimensional systems with realistic defects
 Journal of computational physics 334 (2017), pp.607619 ISSN: 00219991 

 English 
 Journal Article 
 Fraunhofer ENAS () 
Abstract
We derive an improved version of the recursive Green's function formalism (RGF), which is a standard tool in the quantum transport theory. We consider the case of disordered quasi onedimensional materials where the disorder is applied in form of randomly distributed realistic defects, leading to partly periodic Hamiltonian matrices. The algorithm accelerates the common RGF in the recursive decimation scheme, using the iteration steps of the renormalization decimation algorithm. This leads to a smaller effective system, which is treated using the common forward iteration scheme. The computational complexity scales linearly with the number of defects, instead of linearly with the total system length for the conventional approach. We show that the scaling of the calculation time of the Green's function depends on the defect density of a random test system. Furthermore, we discuss the calculation time and the memory requirement of the whole transport formalism applied to defective carbon nanotubes.