How to set parameter “fsthick” ?

Discussion around electron-phonon

Moderator: hlee

Post Reply
dhw
Posts: 11
Joined: Thu Dec 03, 2020 7:46 am
Affiliation: none

How to set parameter “fsthick” ?

Post by dhw »

Hello everyone:
I have a question to ask you, that is, how should I set the fsthick parameter when I calculate the electro-acoustic coupling and superconducting gap? Is it related to
k + q = k'
? I can't find any analytical material about them.Have clear this knowledge elder broad to help answer it? thank you!

Sincerely,
dhw

hpaudya1
Posts: 101
Joined: Tue Mar 21, 2017 7:11 pm
Affiliation:

Re: How to set parameter “fsthick” ?

Post by hpaudya1 »

Hi dhw,

You need to do convergence tests for few values of fsthick. You can start from 4 times the maximum phonon frequency of your system (many times I have found we do not need to go beyond). For example, in MgB2, the maximum phonon frequency is around 100 meV, so we have used fsthick = 0.4 eV, which is 4 times the maximum phonon frequency (see: https://gitlab.com/QEF/q-e/-/blob/devel ... epw.in#L33).
I hope it helps.

PS) Could you please sign your name and your affiliation in your future posts.

Happy EPWing,
Hari

dhw
Posts: 11
Joined: Thu Dec 03, 2020 7:46 am
Affiliation: none

Re: How to set parameter “fsthick” ?

Post by dhw »

Dear Hari ,
Ok, thank you.  The solution is very helpful to me.  But is there any advice to explain the problem from a theoretical perspective?
Sincerely,
dhwu

Post Reply