Effective band structure calculation

[Roc2019]

Dear Developers,

Is there any newest tutorial about the Effective band structure calculation that is compatible with the newest version such as QuantumATK 2023.09 version? 

Thanks so much.

[Anders Blom]

No, but what problems did you encounter in the old one, so we can guide you around them?

[Roc2019]

No, but what problems did you encounter in the old one, so we can guide you around them?

Dear Dr Blom,

How to input the primitive cell structure  through the GUI of the latest 2023.09 version in the calculation of Effective band structure？ 

Thanks。

Roc

[Anders Blom]

Thank you for that question, it clearly needs to be clarified in the new framework.

1. Start with your primitive structure in the Builder. Give it an obvious name, like "GaAs primitive"
2. Still in the Builder, create the supercell, e.g. by repetition and randomization etc. Name it accordingly, like "InGaAs supercell"
3. Send the supercell to the Workflow Builder
4. Insert a calculator block and the Effective Band Structure block
5. As you see now, there is a warning (error, really) that the primitive configuration is missing
6. Insert a "Configuration(s)" block
7. Move it to the top of the script
8. Open "Configuration(s)" block (double-click), and click the +. By default, this let's you add structures from the Builder stash file. Pick the primitive structure.
9. Optional: drag the inserted configuration out of the Configurations block, and above it. Then you can delete the Configuration(s) container
10. Optional, but nice for clarity: Select each configuration block, press F2 and rename them "supercell" and "primitive" respectively. Now you can easily check that the primitive cell is assigned to the corresponding keyword in the EffectiveBandstructure call in the script

Not entirely obvious without guidance, I agree, but you can now save the workflow and reuse it for many different structures.

[Anders Blom]

Even internally we are still learning all the advanced features of the Workflow Builder :-)

After I set up the flow as indicated above, I realized you can click the colored dots on the right-hand side of each block, and control the "wiring". So if you click the dots of the EffectiveBandstructure, you will see explicitly which configurations are connected as primitive and supercell (and what the colors mean), and you can even change it.

See picture

[AsifShah]

Dear Anders Blom,
While I opened this post for other reasons, but thanks for posting the information about colors in the workflow. Helped resolve my doubt since long. 

but it also put me in doubt when you said, we are internally learning about workflow features? Aren't you the ones who introduced this feature, how come you are learning about it? Is workflow an art of AI?
Also, please include these learning in Manual, that would help a lot many QATK users.

[Anders Blom]

Oh no, not AI (at least not yet), I just meant the features were developing quickly and I personally have not had the time to explore all possible workflows for various tasks, like the example we discussed here.
Agree on the manual; there is some info already (https://docs.quantumatk.com/guides/workflows_manual/workflows_introduction/workflows_introduction.html) but we should update it, it seems.

[AsifShah]

Thanks for sharing.

Yes please update the manual, especially on the MLFF training section.