Error to calculate the relationship between superconducting gap ang temperature

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jAcK
Posts: 2
Joined: Wed Aug 12, 2020 1:51 am
Affiliation: PHD candidate

Error to calculate the relationship between superconducting gap ang temperature

Post by jAcK »

Error Description :
For this case, Tc is about 7K,and gap is 1.2meV. And I set 1K,5K,9K,13K in epw.in, Tc is about 7K in the output of epw.out, But
the code doesn't stop at 9K, It calculate all of the temperature above, and the superconducting gap in the XX.imag_aniso and
XX.imag_aniso_gap0 are the same, all of the gap are 1.2meV in 1K,5K,9K,13K.
I don't konw what happened and how to modify the parameters.
But I notice that wscut is 1.0eV in epw.in that might cause this error?
And another thing puzzle me is the pade _aniso file only output XX.pade_aniso_009, X.pade_aniso_013; XX.pade_iso_009.00,
XX.pade_iso_013.00; XX.qdos_009.00,qdos_013.00 ; which doesn't output XX.pade_iso_001.00, XX.pade_iso_005.00. and XX.qdos_001.00
XX.qdos_005.00

Thanks very much.

jAcK
Posts: 2
Joined: Wed Aug 12, 2020 1:51 am
Affiliation: PHD candidate

Re: Error to calculate the relationship between superconducting gap ang temperature

Post by jAcK »

And I test set wscut to 0.1, this error also exists.

Then I set temp to be 50K, the code also runs succefully, and the gap is also 1.2meV for 50K.

Does this means the temp doesn't work ????

hpaudya1
Posts: 190
Joined: Tue Mar 21, 2017 7:11 pm
Affiliation:

Re: Error to calculate the relationship between superconducting gap ang temperature

Post by hpaudya1 »

Hi Jack,

The Tc what you see in your epw output is the Allen-Dynes estimate, and that may be different in the isotropic/anisotropic calculations. The code does not stop at any temperatures, but may not converge (you may have seen a warning in your output). I am not sure what is your maximum phonon frequency, but wscut is recommended be at least four times the maximum phonon frequency (I think it is better to do convergence test to set up for your system).

For the pade output, I recommend to use "iverbosity = 2"in your input.

As always, it is better to have more input/output information to give more explicit solution.

Best,
Hari Paudyal

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