EPW Forum

I am trying to calculate the electron phonon coefficient (lambda) in a 2D structure. I have been supplying the Fermi energy value in the epw input files using the flag : efermi_read=.true. In the 'crystal.fmt' file, the number of electrons in my system is "22.000". However, when I run the ...

Dear all, I am trying to calculate the effect of doping on the electron phonon coupling coefficient (lambda). I want to make sure that the technique I am thinking of is correct: 1- First change the number of electrons in the crystal.fmt file and obtain the new Fermi energy. 2- Re-run calculations fo...

Dear all, I am trying to calculate both the electron and hole relaxation times from the imaginary electronic self energy obtained from EPW. I have summed over all energies above the Fermi energy to obtain the electron relaxation time \tau{el} and summed over all valence bands to obtain the hole rela...

Dear Roxana,

Sorry for the late reply. It worked with QE-6.3 and EPW5.0 by using the developers version. I am running some calculations at the moment with these versions. When they are done, I will donwloaded the latest versions and if the problem resurfaces , I will let you know.

Thank you

Dear all, I am running EPW for a system where exclude_bands have to be used and I am getting the 'famous' error: " Error: dis_spheres_first_wann is larger than num_bands-num_wann+1". I have read that I need to download the developers version of Wannier90 and this should solve the problem. ...

Thank you for your answer, I just got two more small questions: 1- What I am doing in my calculations is that I am calculating the average of $\tau_{n,k}$ over all bands and and all points for say the 11 Wannier functions I considered and using it in subsequent transport calculations. Is this correc...

Dear all, I am trying to compute transport properties for some materials (Seebeck, electronic conductivity, thermal lattice conductivity, etc). The code I am using allows to compute these properties for different electron/hole concentrations. However I have been setting the electronic lifetime ($\ta...

It seems it worked when both nqf and nkf grids were set to 100 x 100 x 1 . The error simply disappeared!

Weird

Dear all, I am trying to test the convergence of lambda w.r.t to the fine phonon grid. I have set my electronic grid to nkf1=90, nqf2=90, nqf3=1. When I try to start the calculations for a fine q grid higher than 90x 90 x 1, the code stops with a lot of "btr" files (I have no idea what the...

Dear Roxana,

Thank you for your reply. I will be looking carefully at the equations in the paper you mentioned.

Regards