Different energy range of band structure in EPW and Quantum espresso

[mirshowkat07]

Dear EPW users

The energy range of EPW band structure and QE is not the same as shown in the attached Figure.
One can see from the Figure that the x-axis for QE bands is from 0 to 1.56 eV, while for EPW bands, it is 0 to 1.8 eV.
Due to this, the EPW bands are not overlapping with the QE band structure.
This type of problem does not occur with phonon band structure which looks fine.
I did many calculations by changing the frozen energy window and which wannier bands to plot, etc., but I am getting similar results every time.

Could anybody help me how to get EPW bands similar to QE?

Best Regards
Showkat
HRI, Allahabad, India.

[hpaudya1]

Hi Showkat,

The x-axis is not the energy axis, it is the wavevector (high symmetry direction).

Could you double-check the co-ordinate of your high-symmetry points in QE band calculation and EPW? It would be to help you if you could provide your input files.

Best,
Hari Paudyal

[mirshowkat07]

Dear Hari Paudyal

Thank you for correcting me; the x-axis is the wavevector, true.
The number of high-symmetry k-points used in EPW calculations is taken from QE bands.out file.
The total number of K-points was the same in both the calculations.
The files are attached herewith.
Thank you for your mail


best regards
SHowkat

[hpaudya1]

Hi SHowkat,

Could you please use crystal coordinates instead 2pi/alat in the EPW calculation?

Best,
Hari

[mirshowkat07]

Dear Hari Paudyal

So nice of you to help me to solve my problem.
The bands are now precisely overlapping by using the crystal coordinates.
Thanks a ton.


best regards
Showkat

[hpaudya1]

Hi Showkat,

Great to know that your problem is solved. There might be some issue with the 2pi/alat coordinate in the implementation, I will have a look at it and update if required.

Happy EPWing,
Hari