Author Topic: Question about Conductance and Transmission pathway?  (Read 4411 times)

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Offline cinda

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If we have more arrows of the transmission pathway between the electrodes means that the have higher conductance? Is there any connection between these two things? Or they are independence?

Offline Anders Blom

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Re: Question about Conductance and Transmission pathway?
« Reply #1 on: June 13, 2012, 13:35 »
You should measure the conductance from the transmission spectrum; the transmission pathways are computed for a particular k-point (and energy), so it might be deceptive, it's just one data point among many. The primary use for the pathways is to figure out where (and how) the current propagates. But sure - the more arrows (above a certain threshold), the more transmission and higher conductivity.

Offline cinda

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Re: Question about Conductance and Transmission pathway?
« Reply #2 on: June 14, 2012, 07:19 »
I calculated one structure, and the Conductance is 56.65 μS. But the transmission pathway is like the attach file. There are just some arrows around the NO2, but the conductance is big. Is that reasonable?

Offline Anders Blom

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Re: Question about Conductance and Transmission pathway?
« Reply #3 on: June 14, 2012, 11:15 »
It's basically impossible to say anything without having a complete picture, not least of the results. At what energy is the pathway computed? How does the transmission spectrum look? How was the conductance computed? Is this at finite or zero bias?

Offline cinda

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Re: Question about Conductance and Transmission pathway?
« Reply #4 on: June 14, 2012, 11:43 »
The energy for pathway is calculated on -0.01eV.
The conductance is used the value of transmission spectrum on 0 eV,
and value of transmission spectrum *77.48091733=the value of conductance
There is no bias and no gat-voltage

The transmission pathway is in the attach file.

Offline Anders Blom

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Re: Question about Conductance and Transmission pathway?
« Reply #5 on: June 19, 2012, 17:07 »
The conductance is consistent with the transmission spectrum, but of course as soon as you apply a bias the current will drop sharply.

The transmission pathways mostly make sense at finite bias; at zero bias there is no current running the system anyway. Maybe we can call it a localized mode...