### How to calculate the electron-phonon scattering rate of a semiconductor?

Posted:

**Thu May 26, 2022 11:40 am**Dear all,

Recently, I read some papers about calculating the lattice thermal conductivity of semiconductor materials, most of them both considering phonon-phonon and electron-phonon scattering (such as, J. Phys. Chem. C 2019, 123, 12001−12006), which greatly reduce the lattice thermal conductivity. I think this phenomenon is very interesting, and I want to explore it further. But the problem that puzzles me for a long time is how to calculate the electron-phonon scattering rate of two-dimensional semiconductor materials with EPW software? What are the core parameters required in epw.in file, and whether need to add " scattering = true, scattering_serta = true and change elecselfen = .false. to true"? I list the parameters used to calculate the phonon self energy in the following. I'm look forward to your pertinent reply and thank you for your help in advance.

Best regards,

Nacy Cui

&inputepw

prefix = 'MoS2',

amass(1) = 95.9400024,

amass(2) = 32.0600014,

outdir = './',

dvscf_dir = '../../ph/save',

filukk = './MoS2.ukk',

elph = .true.

epwwrite = .true.

epwread = .false.

system_2d = .true.

fsthick = 6

temps = 300

degaussw = 0.01

degaussq = 0.02

elecselfen = .false.

phonselfen = .true.

delta_approx= .true.

wannierize = .true.

nbndsub = 11,

num_iter = 0,

iprint = 2,

dis_win_max = 4.4

dis_win_min = -8.0

dis_froz_min = -7.0

dis_froz_max = 4.0

proj(1) = 'Mo:l=2',

proj(2) = 's:l=1'

wdata(1) = 'bands_plot = .true.'

wdata(2) = 'begin kpoint_path'

wdata(3) = 'G 0.000 0.000 0.000 M 0.000 0.500 0.00'

wdata(4) = 'M 0.000 0.500 0.000 K -0.333 0.667 0.00'

wdata(5) = 'K -0.333 0.667 0.000 G 0.000 0.000 0.000'

wdata(6) = 'end kpoint_path'

wdata(7) = 'bands_plot_format = gnuplot'

nkf1 = 108

nkf2 = 108

nkf3 = 1

nqf1 = 108

nqf2 = 108

nqf3 = 1

nk1 = 18

nk2 = 18

nk3 = 1

nq1 = 6

nq2 = 6

nq3 = 1

/

14 cartesian

0.000000000000000E+00 0.000000000000000E+00 0.000000000000000E+00

0.000000000000000E+00 0.115470053837908E+00 0.000000000000000E+00

0.000000000000000E+00 0.230940107675815E+00 0.000000000000000E+00

0.000000000000000E+00 0.346410161513723E+00 0.000000000000000E+00

0.000000000000000E+00 0.461880215351631E+00 0.000000000000000E+00

0.000000000000000E+00 -0.577350269189539E+00 0.000000000000000E+00

0.999999999999920E-01 0.173205080756862E+00 0.000000000000000E+00

0.999999999999920E-01 0.288675134594769E+00 0.000000000000000E+00

0.999999999999920E-01 0.404145188432677E+00 0.000000000000000E+00

0.999999999999920E-01 0.519615242270585E+00 0.000000000000000E+00

0.199999999999984E+00 0.346410161513723E+00 0.000000000000000E+00

0.199999999999984E+00 0.461880215351631E+00 0.000000000000000E+00

0.199999999999984E+00 0.577350269189539E+00 0.000000000000000E+00

0.299999999999976E+00 0.519615242270585E+00 0.000000000000000E+00

Recently, I read some papers about calculating the lattice thermal conductivity of semiconductor materials, most of them both considering phonon-phonon and electron-phonon scattering (such as, J. Phys. Chem. C 2019, 123, 12001−12006), which greatly reduce the lattice thermal conductivity. I think this phenomenon is very interesting, and I want to explore it further. But the problem that puzzles me for a long time is how to calculate the electron-phonon scattering rate of two-dimensional semiconductor materials with EPW software? What are the core parameters required in epw.in file, and whether need to add " scattering = true, scattering_serta = true and change elecselfen = .false. to true"? I list the parameters used to calculate the phonon self energy in the following. I'm look forward to your pertinent reply and thank you for your help in advance.

Best regards,

Nacy Cui

&inputepw

prefix = 'MoS2',

amass(1) = 95.9400024,

amass(2) = 32.0600014,

outdir = './',

dvscf_dir = '../../ph/save',

filukk = './MoS2.ukk',

elph = .true.

epwwrite = .true.

epwread = .false.

system_2d = .true.

fsthick = 6

temps = 300

degaussw = 0.01

degaussq = 0.02

elecselfen = .false.

phonselfen = .true.

delta_approx= .true.

wannierize = .true.

nbndsub = 11,

num_iter = 0,

iprint = 2,

dis_win_max = 4.4

dis_win_min = -8.0

dis_froz_min = -7.0

dis_froz_max = 4.0

proj(1) = 'Mo:l=2',

proj(2) = 's:l=1'

wdata(1) = 'bands_plot = .true.'

wdata(2) = 'begin kpoint_path'

wdata(3) = 'G 0.000 0.000 0.000 M 0.000 0.500 0.00'

wdata(4) = 'M 0.000 0.500 0.000 K -0.333 0.667 0.00'

wdata(5) = 'K -0.333 0.667 0.000 G 0.000 0.000 0.000'

wdata(6) = 'end kpoint_path'

wdata(7) = 'bands_plot_format = gnuplot'

nkf1 = 108

nkf2 = 108

nkf3 = 1

nqf1 = 108

nqf2 = 108

nqf3 = 1

nk1 = 18

nk2 = 18

nk3 = 1

nq1 = 6

nq2 = 6

nq3 = 1

/

14 cartesian

0.000000000000000E+00 0.000000000000000E+00 0.000000000000000E+00

0.000000000000000E+00 0.115470053837908E+00 0.000000000000000E+00

0.000000000000000E+00 0.230940107675815E+00 0.000000000000000E+00

0.000000000000000E+00 0.346410161513723E+00 0.000000000000000E+00

0.000000000000000E+00 0.461880215351631E+00 0.000000000000000E+00

0.000000000000000E+00 -0.577350269189539E+00 0.000000000000000E+00

0.999999999999920E-01 0.173205080756862E+00 0.000000000000000E+00

0.999999999999920E-01 0.288675134594769E+00 0.000000000000000E+00

0.999999999999920E-01 0.404145188432677E+00 0.000000000000000E+00

0.999999999999920E-01 0.519615242270585E+00 0.000000000000000E+00

0.199999999999984E+00 0.346410161513723E+00 0.000000000000000E+00

0.199999999999984E+00 0.461880215351631E+00 0.000000000000000E+00

0.199999999999984E+00 0.577350269189539E+00 0.000000000000000E+00

0.299999999999976E+00 0.519615242270585E+00 0.000000000000000E+00