EPW Forum

Dear developer, I have observed that the real part of g is larger than |g|. The relevant input and output are listed below. After examining the elphon.f90 file, I noted that |g| is printed as ryd2mev * epc_unsym(ibnd, jbnd, nu) at line 1716, where epc_unsym(ibnd, jbnd, nu) equals to sqrt(gamma/(2 ...

The issue has been resolved by changing the etf_mem parameter from 0 to 1, after which EPW began functioning normally. Both QE and EPW were compiled with AMD AOCC, which causes EPW to fail to return reliable information when it malfunctions.

Dear, I am using EPW to interpolate the electron-phonon matrix. The system I am studying contains two atoms. The k-mesh for the non-self-consistent field (nscf) calculation is 24×24×1, and the q-mesh for the phonon calculation is 12×12×1. The number of Wannier functions (num_wann) as well as nbndsub ...

Dear, I aim to compare the electron-phonon coupling matrix elements (g-vertex) computed by EPW and DFPT. For the DFPT calculations performed with ph.x, I note from the source code elphon.f90 that the dynamical matrices (dyn) used to construct the g-vertex are obtained without applying the Acoustic ...

Dear,
Thank you.
Best

Dear, Thank you for your helpful response. I've noticed the larger spread of the Wannier functions and was attempting to generate them by including both valence and conduction bands. However, I was unsure how to properly exclude the conduction bands. Your reply has provided me with a clear guideline ...

Dear,
Thank you for your response. I have uploaded all input files.
The wannierization is implied with the "wannier_plot_supercell = 6 6 2", and the proj is set to P's p orbit. The fitting bands agree well with the DFT.
The polaron I calcualted is hole polaron.

Dear, I am attempting to calculate the hole polaron in two-dimensional blue phosphorus (blue P). However, during the EPW calculation, an error message appears: "Non-physical solution, check initial guess and convergence." The monolayer blue P structure contains two equivalent P atoms. The valence ...

Dear, Thank you for your response. EPW works well after I change the 'longrange' to 'longrange_only'. I want to ask another question about epw. If I set 'longrang_only', only the longrange part of e-ph is considered. If I set 'shortrange', only the shortrange part of e-ph is considered. If I set ...

Dear, I want to check the impart of longrange, shortrange and lpolar tags. The input files are obtained from the tutorial Files of Summer School 2024. The system is BN. And I add the prtgkk tag and shortrange (or longrange) tag to obtain the ep vertex. The lpolar=.true. and shortrange=.true. works ...