EPW Forum

Dear Anish, As you mentioned, "angles between k and k+q" is arbitrary due to the equivalence between k and k + G, G being the reciprocal lattice vector. However, if it can not be well-defined, it is most likely meaningless for research. So you'd better describe what you're calculating and why you ...

Hi,

The calculation of carrier concentration assumes the Fermi level is in the gap. The concentration at the order of 10^21 is rather high. So it may be near the band edge. Please check the doped Fermi level carefully. Or you can start from a lower carrier concentration, like 10^16

Best,
Zhe

Hi, I have two comments on the input file. 1. 1.E-15 cm^-2 is far too large for a 2 dimension system. It can be found that the doped Fermi level ( -6.8129 and -1.9614) is far from the input one (-4.228393) 2. As we know, graphene is a semi-metal, which is incompatible with carrier and ncarrier. They ...

Dear Yan, A well symmetry of energies or velocities relies on a well Wannierization. We have a well-tested example of silicon in PHYSICAL REVIEW RESEARCH 3, 043022 (2021) and you can download input files from https://archive.materialscloud.org/record/2021.94 I did the same test as you described with ...

Dear Sara,

I find that you used different types of pseudopotential(PP) for Mo(NC) and S(US).

Maybe you could check the band structure and replace one of PPs.

Best Regards

Zhe

Dear Sara, Sorry, I misunderstood your purpose before. (1)If you just want to calculate the e-ph matrix, the Ef is meaningless. It works on the calculation of mobility by changing the Fermi-Dirac distribution. Maybe you can check the wannierized band structure and the convergence of e-ph in real ...

Dear Sara, (1) Fermi energy depends on doping. The smearing method can only calculate the undoped case. Actually, it is the relation between Ef and carrier concentration that matters. (2) Sorry for my poor expression. I mean, if you set fsthick = 15.0, the problem below will disappear. A selecq.fmt ...

Dear Sara, In my opinion, (1) You don't need to set the Ef in the middle of the gap. If you want to calculate an N-type MoS2, a Ef near the conductive band might be better. (2) You need a larger fsthick. EPW filter those q points that both E_k and E_k+q are within Ef +/- fsthick for at least one k ...

ilias-serifi wrote:HI


where can i found this new version of epw i enter to the home page and i didn't found EPW v5.1.0



Best regard

Hi,

You just need to download the entire QE-6.4.

http://www.quantum-espresso.org/news-ev ... esso-v-6-4

Best Regards

Update
I run EPW without parallel and this problem disappears.

I think this problem is due to a bug of the parallel of wannier90 as library.