Features and Functionalities¶
Can you recommend some reading material on the background of the NEGF method?¶
For first reading, there are several good introductions published by Supriyo Datta.
The book is an introduction to NEGF which is not too advanced.
There is a more advanced book, [DattaETMS1995]. Chapter 8 is a good introduction.
A rather simple article is [DattaSuperlatticesMicrostructures2000].
[Jirauschek2014] describes the NEGF method in Section VIII.
Other books or articles on NEGF usually require advanced quantum mechanics or quantum field theory.
What is the difference between the “RealSpaceModes” and “EnergyEigenstates” in the output folder?¶
“EnergyEigenstates” refers to the energy eigenstates of given heterostructure, obtained by diagonalizing the Hamiltonians (at each in-plane k point). “RealSpaceModes” are the position eigenstates within the subspace obtained after applying the axial cut-off energy (see Reduced real space basis). These position eigenstates are used as a basis in the NEGF calculation.
Note
“RealSpaceModes” depends on Axial energy cut-off. Increasing the axial energy range localizes the position eigenstates more.
What are the meanings of “Check normalization of spectral function = …” and “Check normalization of lesser Green’s function = …” in the log file?¶
If the final values differ significantly from 1, these are indications that some states are not correctly accounted by the energy grid: either EnergyGridSpacing is too coarse, and/or the energy range is not correctly defined. See Energy range of the Green’s functions for how to resolve the latter issue.
Last update: 30/10/2024