energy contour plot for band structure

[jchang]

Hi,

I wonder if there is a way to generate energy contour plot for the BZ as in the attached file.

Thanks.
jiwon

[Anders Blom]

See https://quantumwise.com/forum/index.php?topic=4821.msg20910#msg20910

[jchang]

Thanks! I will try the script you posted there.

jiwon

[jchang]

Hi Ander,

I could successfully modify your scrip for contour plot.
But I have one question for you.

In the attached contour plot, I plotted CB and there are six CB minimum valleys along Gamma to M.
For those valleys, I expected ellipsoidal contour plots, but as shown in the plot, contour line is getting sharper along G to M lines.
And same things around M point, I expected ellipsoidal contour plots, but what I see is somewhat sharp points along G to M.

I think it could be an error from interpolation.
I did band structure calculations with dense k points, but no change.

Do you have any ideas about this?


Thanks.
jiwon

[Anders Blom]

Why did you expect ellipsoidal?

[jchang]

Hi, Anders

I tried to reproduce result reported in literature.
Would it be good to try other pseudopotentials and basis sets?


jiwon

[Petr Khomyakov]

You have provided no information about your system of interest and the literature you are referring to, so it is hard to give any concrete answer to your questions.

[jchang]

Hi,

What I want to reproduce is shown here.
http://ieeexplore.ieee.org/abstract/document/8110697/

In Fig3(c) and (d), valley looks ellipsoidal.

Please give me some advices.

Thanks.
jiwon

[Petr Khomyakov]

To me Fig. 3(c) looks pretty much as the figure you have enclosed. It is just the color scheme that is different. Given that the authors have used a different computational approach, the two results seem to be in a fair agreement.

[jchang]

Thanks for your input.

Yes, it looks pretty much same. But along G to M line, I think contour line around M is orthogonal to line connecting G and M in paper.
But in my figure, it seems not (it is notched). So I suspected something is wrong in interpolation or in my calculation itself.

Thanks.
jiwon

[Anders Blom]

Given that you use DFT and the paper uses tight-binding, I'd say that explains the difference.

[jchang]

In the paper, they matched TB with DFT shown in Fig 1.
Almost same TB band structure with DFT.

It is enough for me if I can confirm that the difference could be caused by interpolation.

Thanks.

[Anders Blom]

And how does your DFT band structure compare to theirs?

[jchang]

HI Anders,

It matches pretty well.

I tried other materials to plot contour plots. I could see those kind of notched contour  in other materials.
I have tested PBE/GGA/FHI. Will try with other options.

jiwon

[Anders Blom]

And maybe try more k-points to reduce interpolation effects