Author Topic: Can Work funtion difference between right and left reflect in EDP?  (Read 5862 times)

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Offline ocdor

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Dear ATK experts,
              I have calculated the EDP(enclosed in attachment). Right and left electrode is 0V,but materials is not in accordence. The work function difference of two electrode materials is 1.1eV. Is my result right?   

Offline Ulrik G. Vej-Hansen

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Please provide more information about the system, preferably also the python script you have used and any log-file from the calculation.

Offline ocdor

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Thank you ! The model and log are enclosed in attachment.

Offline Ulrik G. Vej-Hansen

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Thank you, but please provide the log-file from the actual calculation, not just the EDP analysis. I apologize that was not clear. Please also provide the python script(s) you have used.

Offline ocdor

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sorry, the total log film is too large to post.

Offline Petr Khomyakov

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Dear ATK experts,
              I have calculated the EDP(enclosed in attachment). Right and left electrode is 0V,but materials is not in accordence. The work function difference of two electrode materials is 1.1eV. Is my result right?

The difference of the EDP values in the left and right electrodes does not need to be zero if the bias voltage is zero, unless the electrodes are identical and the system has a mirror symmetry, but this is not the case. So, I guess the result is correct.

I would, however, increase the central region of your device, as the electrode extensions now seems to be directly coupled to the overlap region where the actual scattering takes place.

Offline ocdor

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Thank you for your careful reply. What's the difference between average and through point?
« Last Edit: July 6, 2017, 04:42 by ocdor »

Offline Petr Khomyakov

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Take a look at the section on "Electron charge density projections" in this tutorial http://docs.quantumwise.com/tutorials/espresso_gui/espresso_gui.html.

Offline ocdor

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Thank you! My Y-axis is  δVE(r) but others are  δVH(r). What's wrong with my calculation or related to my calculation setup?
« Last Edit: July 6, 2017, 09:27 by ocdor »

Offline Petr Khomyakov

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What version of ATK are you using? In ATK2016, we had changed definition of the Electrostatic and Hartree Potentials as well as the related Differences. New Hartree potential is (-1) Old Electrostatic potential, and  New Electrostatic potential is (-1) Old Hartree potential. The units of the New Hartree  potential and New Electrostatic potential are eV and Volt, respectively.

Offline ocdor

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Thanks, my ATK version is 2016.

Offline Petr Khomyakov

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If ATK-2016, then your potentials are defined in new convention that we  will keep for all the future releases, including the newest ATK-2017.0  that is already available for download on our website.