How to obtain contributions of different phonon modes to carrier scattering

[joshie]

Hi everyone:
Recently, I noticed the underlying mechanism of carrier mobility. It can be well understood by contributions of different phonon modes to carrier scattering (or mode-resolved scattering rates) published in Nano Lett. (2019, 19, 1774-1781, Dimensional Crossover in the Carrier Mobility of Two-Dimensional Semiconductors: The Case of InSe). The authors, in their work, employed the EPW code to deal with the issue. However, I try to obtain mode-resolved scattering rates by changing input parameters or modifying the source code but ultimately failed.

I followed someone's suggestion 'set the keyword "iverbosity = 3' in my EPW input file, but the results did not show anything related to the mode-resolved scattering rates. I also changed the transport.f90 in the SCR folder, and each mode's contribution can be output separately. As a result, both methods can't achieve the desired effect.

Can anybody know how to get the mode-resolved scattering rates excellently?

[sponce]

Hello joshie,

You are correct, in the public version of EPW the "iverbosity = 3" keyword will only give you the mode resolve self-energy, which is closely linked with the scattering rates.

We have implemented the mode resolved scattering rates and and its contribution to the mobility as part of a larger implementation that will be released hopefully soon(ish).

If you want to get it sooner, you can modify the print_ibte subroutine of the io_transport.f90 file.
Then look for how the inv_tau.fmt file is created (total relaxation time) and adapt to make it mode resolved.

Hope this helps.

Best wishes,
Samuel

[jyoti23]

Hi Samuel,

Thank you for the explanation.

I wanted to check whether the mode-resolved scattering rate feature has now been added to the public EPW release. If yes, could you please let me know which version includes it?

If yes, could you kindly explain the recommended procedure to implement it?

Thanks,
Jyoti