Search found 7 matches

by fale li
Tue Jan 21, 2025 5:55 am
Forum: General discussion
Topic: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high
Replies: 9
Views: 8540

Re: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high

Dear Li, Thank you for sharing the spatial decays. They appear to be well localized with respect to the lattice vectors. While it might be possible to slightly improve the spatial localization by increasing the number of Wannier orbitals, it is unlikely that this is the main cause of the ...
by fale li
Mon Jan 20, 2025 10:31 am
Forum: General discussion
Topic: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high
Replies: 9
Views: 8540

Re: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high

Dear Li, I initially misunderstood that you were using EPW for Pb, but you are actually working with TaNbHfZr, correct? To rule out the possibility that the issue originates from the orbitals, it would be prudent to re-examine them, especially when dealing with a new system in EPW. Have you plotted ...
by fale li
Thu Jan 16, 2025 8:03 am
Forum: General discussion
Topic: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high
Replies: 9
Views: 8540

Re: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high

Dear Li, Even if the Wannier bands closely reproduce the DFT bands, the Wannier orbitals may not be ideal for EPW. To effectively interpolate the electron-phonon interaction, the Wannier orbitals must be spatially localized. I strongly recommend repeating the calculations using the s and p orbitals ...
by fale li
Fri Jan 10, 2025 2:12 pm
Forum: General discussion
Topic: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high
Replies: 9
Views: 8540

Re: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high

Dear Li, I guess your calculations are collinear and do not account for spin-orbit interaction, which may lead to an overestimation of the Allen-Dynes Tc compared to its expected converged value. With this in mind, I have a few concerns: 1. If the target system is truly fcc Pb, the p orbitals of Pb ...
by fale li
Mon Jan 06, 2025 9:41 am
Forum: General discussion
Topic: The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high
Replies: 9
Views: 8540

The superconducting transition temperature calculated from the superconducting gap Δ(T) is too high

Dear all, When I calculated the gap function and the superconducting transition temperature by solving the isotropic Migdal-Eliashberg equation with the example of fcc Pb, the results obtained are as follows: Finish reading a2f file Electron-phonon coupling strength = 3.2617374 Estimated Allen-Dynes ...
by fale li
Mon Aug 05, 2024 2:50 am
Forum: Running the code
Topic: Calculation of the intensity of lambda (ele-phon coupling constant) is too big
Replies: 2
Views: 7678

Re: Calculation of the intensity of lambda (ele-phon coupling constant) is too big

Hi Sabya I think the energy band diagram fitted by my Wannier function is still good. I attach the picture.I have tried to increase the coarse grid quantities, and the lambda will change but it is still unusually large.I have used pbe, pbesol and uspp pseudopotentials to calculate, but it has no ...
by fale li
Fri Jul 26, 2024 12:02 pm
Forum: Running the code
Topic: Calculation of the intensity of lambda (ele-phon coupling constant) is too big
Replies: 2
Views: 7678

Calculation of the intensity of lambda (ele-phon coupling constant) is too big

Dear all, When I calculate the EPC strength (lambda) of BCC V according to the example that pb has no soc, the result in epw.out is extremely large, reaching 3799,and the lambda_tr reaching 3357. I found that someone in the forum had encountered this problem before, and he solved it by changing the ...