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