Hello Hari,
Yes, those values are very high indeed, but I am forced to increase wscut otherwise I get negative gap values again.
Is there maybe something else I can try?
Best,
Mikhail
Search found 50 matches
- Mon Dec 27, 2021 6:14 pm
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
- Thu Dec 23, 2021 11:31 am
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
Re: Gap energy abruptly goes negative at high temperatures
Hello Hari, At the moment, for 16 K temperature I am trying Total number of frequency points nsiw( 1) = 550 Cutoff frequency wscut = 4.7690 with phonons not higher in energy than 200 meV. I am trying such high value because Total number of frequency points nsiw( 1) = 450 Cutoff frequency wscut = 3.9...
- Mon Dec 20, 2021 2:21 pm
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
Re: Gap energy abruptly goes negative at high temperatures
Hello Hari, Your advice seems to be working, thanks a lot ! The only thing is that the higher the temperature I set in the calculation the more frequencies I need to make the gap positive. Is this normal behavior ? For all my previous materials, I used to just set a certain wscut (a very small one c...
- Wed Dec 15, 2021 6:59 am
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
Re: Gap energy abruptly goes negative at high temperatures
Hello Hari, I did those tests already, and you are absolutely right: mustar 0 solves the problem. And when I start increasing it, the problem appears again at a value around 0.1(likely less than that). Unfortunately, results with mustar=0 are hardly suitable for a research, and there must be a reaso...
- Sat Dec 11, 2021 8:28 am
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
Re: Gap energy abruptly goes negative at high temperatures
Hello Hari,
Here are the pictures you requested:
https://ibb.co/XV4C5CC
https://ibb.co/Qp0XTfg
Best,
Mikhail
Here are the pictures you requested:
https://ibb.co/XV4C5CC
https://ibb.co/Qp0XTfg
Best,
Mikhail
- Fri Nov 19, 2021 1:57 pm
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
Re: Gap energy goes negative at high temperatures
A little update to the question. In order to understand the problem better, I computed the EPC projected on the phonon band structure. and there is something I am concerned about. In the output file(see below) I see that lamda_tr and gamma_tr go negative. I think I have never seen it before. Could y...
- Thu Nov 11, 2021 10:08 pm
- Forum: Running the code
- Topic: Gap energy abruptly goes negative at high temperatures
- Replies: 12
- Views: 14999
Gap energy abruptly goes negative at high temperatures
Dear experts and users, I calculated superconducting properties of a material in EPW 5.4 and 5.1, and there is the same problem I see. The isotropic results Electron-phonon coupling strength = 0.8613774 Estimated Allen-Dynes Tc = 17.174912 K for muc = 0.13000 Estimated w_log in Allen-Dynes Tc = 33.0...
- Fri Nov 05, 2021 9:28 am
- Forum: Running the code
- Topic: Gap distribution yields a gap almost at zero energy.
- Replies: 1
- Views: 3573
Gap distribution yields a gap almost at zero energy.
Dear experts and users, I was calculating superconducting properties of a material, and I found that the gap distribution yields a gap almost at zero energy. The gap distribution : https://ibb.co/p4jDR3f It looks a bit odd. Do you think it can be correct ? I checked the wannierization/spreads, and t...
- Wed Oct 06, 2021 7:59 pm
- Forum: Running the code
- Topic: Anomalously large electron-phonon coupling
- Replies: 1
- Views: 2897
Anomalously large electron-phonon coupling
Dear experts and users, I have encountered a problem with anomalously large electron-phonon coupling in my calculations. I have read several posts concerning this problem, and done several checks to see if something was wrong. 1. Wannierization is alright. The spreads are small, and the W90 bands ar...
- Tue Oct 05, 2021 11:53 am
- Forum: Running the code
- Topic: Calculation gets frozen during/after wannierization stage
- Replies: 3
- Views: 3703
Re: Calculation gets frozen during/after wannierization stage
UPDATE: the was no problem. I made a mistake in the initial projections, so naturally the whole convergence of the disentanglement procedure was very bad. In 500 cycles it was still of the order to 10^(-1), but surprisingly it gave me very good bands (this actually confused me). But even with the ba...