EPW phonon bandstructure inconsistent with QE results

[Qiaolin]

Dear all,

Recently, I try to use EPW to study transport property. The phonon dispersion with SOC agrees with the QE results, but the LO and TO frequency of G point is still denegrated. I have set " lpoar = .true. lifc = .true. asr_typ = 'crystal' "



Is this a normal phenomenon? I put my input in the following:
https://github.com/Isabellelin/g_matric ... ain/SiC_ph

Thanks in advance if anyone can help the problem.

Sincerely,
Qiaolin

[hlee]

Dear Qiaolin:

Which version of EPW are you using?
In addition, could you provide me with the file of LGXKG_50.txt ?

Sincerely,

H. Lee

[Qiaolin]

Hi Mr. Lee,

The version of QE and EPW I used are 6.7 and 5.3.1.
LGXKG_50.txt : https://github.com/Isabellelin/g_matric ... XKG_50.txt

Best Regards,
Qiaolin

[hlee]

Dear Qiaolin:

I think that this difference can't be avoided since EPW doesn't include the non-analytic term which results in the LO-TO splitting in SiC.
For example, if you add to matdyn.in "loto_disable = .true." (with loto_disable set to true, the non-analytic term is not included in matdyn.x, even the result from matdyn.x doesn't show the LO-TO splitting at q=0 in SiC by skipping the call to the subroutine of nonanal. Please see https://gitlab.com/QEF/q-e/-/blob/devel ... n.f90#L618 .

Sincerely,

H. Lee