Energy-position resolved Electron density Spectrum for analyzing Tunneling

[ruyam]

Dear Sir,

In a paper whose results were obtained using ATK, I saw a picture attached below. I was wondering how to plot such a figure in ATK ?

[Anders Blom]

Which paper? It looks since some projected value of density per atom, not sure how this is defined though. I doubt this is with ATK because the transport axis is X, in ATK it's always Z.

[ruyam]

In paper (http://arxiv.org/pdf/1408.6003v1.pdf), though another simulation tool is also mentioned in the references along with ATK. I wanted to know how to get a similar figure to understand the tunnelling phenomenon in devices

[Anders Blom]

It is certainly not ATK, although it has the same features needed. The figures are highly confusing because they claim to show something energy-resolved, but there is not indication of how the energy enters, the legend talks about "charge", not energy. There is also no clear definition of the concept "energy-position resolved electron density spectrum". If we knew what that was, I'm sure it can be computed in ATK and plotted like this (you just color the atoms by this quantity).

[ruyam]

So Sir, how can I understand pictorially how a tunneling phenomenon occurs. Can we do that using ATK? Suppose for an interface between different metal/semiconductor, there is current flow and I need to capture it pictorially to verify from which regions does the current flow at the contact, etc.
Is there some other analyzer to cater this problem in ATK?

 

[Anders Blom]

I don't think the plot we are discussing explains anything about "how" the tunneling occurs. What you can do in ATK, instead, is to plot e.g. the transmission pathways like in the tutorials: http://quantumwise.com/documents/manuals/latest/VNLTutorial/index.html/chap.gnr.html