How to choose proper "Effective coulomb potential"?

[leedairo]

Dear users,

In Migdal-Eliashberg equation, (and In EPW) electron-electron repulsion is introduced by "Effective coulomb potential (in EPW, muc)" and it greatly affects the results (Tc or paring gap ..).

How can we choose proper effective coulomb potential value?

Is there a good idea to estimate this value for a particular material?

Thanks,
Seungjun LEE

[roxana]

Hi Seungjun,

You can take a look at our article:
http://www.nature.com/articles/srep21414

In this case muc was estimated using the screened Coulomb interaction within the random phase approximation (this part was not done with the EPW code).

Best,
Roxana

[leedairo]

Dear roxana,

Thank you for kind reply,

I will read the article.

Thanks,
Seungjun LEE