plot amplitude and phase in k space of envelope function and transition matrix elements

[WEIW]

Dear developers,
I want to plot amplitude and phase in k space of envelope function and interband optical transition matrix elements, as attached below.
How can I achieve it using yambopy?
Best,
Liu

[palful]

Dear Liu,

Plotting dipole strengths and envelope functions in modulus is a standard capability of yambopy and it is covered this tutorial.

Plotting the phase is not standard, but you can start using yambopy as a python library to read the envelope function (in the form of A-coefficients) as complex numbers, as explained in the tutorial. Then, you will have to do your own script for the analysis.
Things to be careful about when talking about the phase: you may need to impose a global gauge on the phases and to pay special attention to the treatment of degenerate states.

Cheers,
Fulvio

[WEIW]

Dear Fulvio,

Thanks for your suggestions! I have written a script by using yambopy as a python library. The script extracts the real part and imaginary part of dipole transition matrix elements, but I don't impose a global gauge on the phase in the whole process. Which step I should impose a gauge? Could you please give me some advices?

And, the figure for amplitude and phase of dipole transition matrix element is attached, but it seems not correct .

Best,
Liu