QuantumATK Forum
QuantumATK => Scripts, Tutorials and Applications => Topic started by: kstokbro on March 10, 2011, 10:51
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Please find a script for calculating moments of the transmission spectrum, from which the following transport coefficients can be obtained:
Seebeck coeffient, thermal conductance, conductance, Peltier coefficient and ZT
It is based on PRB 73, 085406 (2006)
Output for Li-H2-Li system:
Conductance = 5.42244762598e-05 S = 0.699842983718 G0
Peltier Coefficient = -1.52243834955e-05 eV/e
Seebeck Coefficient = -5.07479449851e-08 V/K = -0.000588904769171 kb/e
Thermal Conductance = 3.89878290707e-10 J/s/K
ZT = 1.0745447041e-07
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Dear Dr. Stockbro,
Can please you also let me know how to generate thermal conductivity script for both diffusive and ballistic electron and phonon transport?
Regards
Sitangshu
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Currently we only support the ballistic electron transport.
We are looking into also supporting also phonon transport and diffusive electron transport.
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Please find an updated script which is more stable than the previous version.
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Dear Sir,
Can you let me know how to run the "script for calculating Seebeck coeffient, thermal conductance, and ZT" ?? I have already the transmission spectrum of Graphene junction (without gate).
Thank you
Sitangshu
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Download the script and open it in the Editor in VNL. Change "test.nc" to the name (with full path, unless it's located in the same directory where VNL starts) and then drop the script on the Job Manager, and run it.
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Here is it as a custom analyzer tool,
Download the script, and drop it on the custom analyzer.
You can now get the transport coefficients by dropping your transmission spectrum on the
file drop zone in the analyzer plugin.
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Dear Sir,
I want to calculate the Seebeck coeffient, the thermal conductance, and then ZT of two probe system by using ATK2008, how to do?
Thank you
Benhu zhou
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ATK2008 is no longer supported, you will need to upgrade to the latest version,
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Dear ATK team,
I'm wondering if we can apply the script for thermoelectric properties only from the transmission spectrum ? I'd like to know if we can get the thermoelectric properties with ATK using a simple procedure (that I want to know ) ?
best
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What is a "simple procedure" compared to using the script?
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I mean by that : to calculate the thermoelectric properties from bandstructure without using transmission spectrum ?
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Thermal transport is, as the name indicates, a transport property and hence must be computed as such. It is however possible (although I can't precisely say how much sense it makes in this case) to compute the transmission spectrum of a perfect material just from the bulk crystal, see http://quantumwise.com/publications/tutorials/mini-tutorials/167.
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Dear all,
is it possible to have the thermoelectric properties for a nanosheet (modified byholes) from the transmission spectrum ? in this case what are the optimized parameters to have the transmission ( such as nA, nB etc...)
best
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The answer to the first question is yes, the second is for you to answer yourself, it can only be found by actually performing the calculations.
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So we don't need electrodes for the transmission spectrum ?
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The comment about computing the transmission from bulk should not be taken out of context. It is only valid for perfectly periodic systems. If you are looking to compute the influence on the transport from a single defect (or several, but not a whole periodic arrangement of them), then you need to set it up as a device.
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Dear ATK team,
I'd like to be sure that with ATK, we can calculate the thermoelectric properties : Seebeck coefficient, the thermal conductance, and then ZT etc.... Following your advice, I have to follow the steps of http://quantumwise.com/publications/tutorials/mini-tutorials/167 in order to get the transmission then calculate the thermoelectric properties using the script. I'd like to know if I have to follow all the steps, such as :
1. Remove one layer, leaving only 3 atoms in the unit cell.
2. Then perform the same transformation to the orthorhombic structure as for graphene above.
3. As an additional step, open Coordinate Tools>Center and center the atoms in all directions.
My system is somehow lamellar ( layers of atomes) but in Bulk. are these steps mandatory ?
I will appreciate much your help
Best
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Hard to say, without knowing the precise system. The steps are not a universal recipe, they are a method to achieve the necessary structure, which needs to follow the universal rule of having the AB plane perpendicular to C which in turn is parallel to Z, the transport direction.
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Dear Everyone,
I am just wondering if it's capable for ATK to calculate the thermal conductance for system with phonon transport now? Then it should be more realistic.
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We are working on this feature, some part will be available in 13.8 coming out during the summer 2013.
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Please find an updated script which is more stable than the previous version.
Dear Dr. Stockbro,
Does the script for calculating Seebeck coeffient, thermal conductance and ZT not consider the influence of electron chemical potential? How to get the ZT with different chemical potential?
Thank you!
Wu-Xing Zhou
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The plugin use pertubation theory, i.e. it is correct for linear responce, i.e. at zero bias where the is a common electrochemical potential.
At finite bias you may calculate the current directly, inputing the temperature of the electrodes. Using finite difference you can then get
dI/dT, dI/DV, and D2I/Dv/dT.