How to run a calculation to get conductance from transmission result?

[Jin-Kyu Choi]

Dear all,
I would like to ask a simple question on how to obtain conductance value from a result file including transmission.

First, I had obtained transmission spectrum using the keywords: [Device-New calculator-TransmissionSpectrum] as in the picture (1_transmission.png).
Then, I tried to obtain further information on the conductance value by running a calculation from the result file of transmission spectrum
I used keywords as [Device-Analysis from File-ElectrostaticDifferencePotential] as in the picture (2_conductance.png).

But, I faced a trouble when I tried to open the result file of the conductance calculation using the window of “Analyzer-IV curve”.
The error message is that:
Traceback (most recent call last):
File ".\zipdir\NL\GUI\Core\Runner.py", line 230, in run
File ".\zipdir\NL\GUI\Tools\CustomAnalyzer\Analyzers\IVCurve.py", line 27, in analyzer
File ".\zipdir\NL\IO\NLSaveUtilities.py", line 243, in nlread
NL.ComputerScienceUtilities.Exceptions.NLValueError: The filename must be given as a string - e.g. "my_file.nc".

Here I have two questions,
(1) is it not possible to calculate conductance value by running a calculation from transmission result?
(2) After just calculating the transmission spectrum [Device-New calculator-TransmissionSpectrum], I can see the current value by drag and drop the result file onto the I-V analyzer. Is this current value is right?

*I know the tutorial on how to calculate I-V (http://www.quantumwise.com/documents/tutorials/latest/ATKTutorialDevice/index.html/chap.iv.html)
I want to know how to run additional calculation to get conductance value from the transmission result.

Thank you very much.
Sincerely,

[Anders Blom]

The conductance is computed directly from the I-V curve, or at zero bias from the transmission spectrum. The electrostatic difference potential has nothing to do with it. You should drop the NC file containing the transmission spectrum (or several) on the dropzone of the Custom Analyzer; it's unclear from your post what you actually drop...?

[Jin-Kyu Choi]

I would like to thank you for your reply.

As you pointed, I droped the NC file containing the transmission spectrum on the dropzone of the "Conductance Plot" in the "Custom Analyzer", then I could have seen the conductance value. (problem solved  )

Previously, to see the conductance value, I droped the NC file of transmission spectrum to the "I-V Curve" in the "Custom Analyzer", then it showed the error message as mentioned in the first post.

Actually, I could have seen the current and conductance values simultaneously by dropping the NC file which was obtained using the keywords: [Device-New calculator-TransmissionSpectrum-ElectrostaticDifferencePotential] in "Script Generator", to the "I-V curve" in the "Custom Analyzer", of which process is introduced in the tutorial in Quantumwise.

Because I do not well understand the nanolanguage or coding in the ATK program, particularly VNL, I do not know the relation between input-keywords and output-results. Anyway now I can see the conductance.

Thank you very much.

[Anders Blom]

Good

The fact that ElectrostaticDifferencePotential is included in the NC file is irrelevant, it's the TransmissionSpectrum that allows you to get the conductance. Your mistake before might have been to only include the potential, or you had the transmission in a different file.