EPW Forum

Dear all, As we know, the electron-phonon coupling matrix g can emerge on the orbital basis and band basis. I was wondering which basis is used in the EPW output. Based on my understanding, the g used in the EPW is on the band basis, which should have an arbitrary phase factor. However, the EPW ...

Dear Dr. Lee,

I see, thanks again!

Best regards,
Zishen

Dear Dr. Lee,

It seems that the code (QE or EPW) uses renormalized phonon frequency in the calculation. It is also a very helpful answer, thanks!

Best regards,
Zishen

Dear Dr. Lee, Thank you for quick reply. As I find that the bare phonon frequency \omega_{q,\nu} obtained by using the previous second formula is different from \omega_{q,\nu} obtained by cDFPT. The major difference is that the \omega_{q,\nu} (LA branch) obtained by using the previous second formula ...

Dear all, According to https://docs.epw-code.org/doc/Electron-phononCoupling.html , the output of the electron-phonon coupling matrix |g| (by prtgkk) is g^SE. 1.png The \omega_{q,\nu} in the denominator is the bare phonon frequency. Although there is no direct output of the bare phonon frequency in ...

Dear Dr. Lee,

I am glad to hear that EPW code will get rid of this bug.
My name is Zishen Wang, a PhD student from the National University of Singapore.

Best regards,
Zishen

Dear H. Lee and Hari, Thank you for your reply. I compared the outputs using cartesian (left side) or crystal (right side), and I found their results are inconsistent with each other at the third point... iq = 1 coord.: 0.0000000 0.0000000 0.0000000 iq = 1 coord.: 0.0000000 0.0000000 0.0000000 ik ...

Hi, I just wonder whether we can use Cartesian coordinates in the EPW5.3.1 Because when I use inputs something like: 3 cartesian 0.0000000 0.0000000 0.0000000 0.3333333 0.0000000 0.0481125 0.0000000 0.3333333 0.0000000 0.0962250 0.0000000 0.3333333 It also doesn't give any errors now. Thanks. Best ...

Dear Dr. Lee, Yes, thanks a lot! May I ask a further question about reducing computational cost or memory usage in prtgkk outputs? As we know, fsthick determines the energy window in which matrixes are interpolated. However, if I want to obtain a full picture of matrix distribution on the band which ...

Dear Dr. Lee, Thank you for your quick response. I used EPW5.3.1 to do the same thing (2D case). iq = 1 coord.: 0.0000000 0.3333334 0.0000000 ik = 1 coord.: -0.3333334 0.3333334 0.0000000 ibnd jbnd imode enk[eV] enk+q[eV] omega(q)[meV] |g|[meV ...