Job control

| prefix | calc_mode | fklist | fqlist | ftemper | debug | yaml_fname | hole | tmp_dir | load_scatter_eph | find_efermi | sampling | cauchy_scale | nsamples | use_mem |

Boltzmann Transport Equation

| boltz_kdim | boltz_qdim | band_min | band_max | boltz_emin | boltz_emax | boltz_nstep | boltz_de | delta_smear | full_ite | phfreq_cutoff | trans_thr |

Polar correction

| polar_split |

Ultra-fast dynamics

| time_step | output_nstep | boltz_init_dist | boltz_init_e0 | boltz_init_smear | solver | boltz_efield | boltz_norm_dist | boltz_acc_thr | boltz_nstep_min | ph_mode_exclude_ranges |

 Job control

JOB CONTROL
prefix

Variable type: string
Default value: ''

Job name prefix. It should be the same as the prefix used in QE.

Mandatory for all calculation types.

JOB CONTROL
calc_mode

Variable type: string
Default value: ''
Options:
'bands'
interpolated electronic band structure (see in the section)
'phdisp'
interpolated phonon dispersions along a given crystal momentum path (see in the section)
'ephmat'
absolute values of the e-ph matrix elements (see in the section)
'setup'
set up transport property calculations (see in the section)
'imsigma'
imaginary part of the lowest-order e-ph self-energy (see in the section)
'meanfp'
e-ph mean free paths for electronic states (see in the section)
'trans'
electrical conductivity and carrier mobility tensors (see in the section)
'trans-pp'
computes Seebeck coefficient (see in the section)
'dynamics-run'
ultrafast hot carrier dynamics (see in the section)
'dynamics-pp'
computes the energy-dependent carrier population as a function of time (see in the section)

Calculation mode. To see the typical input files for different calculation modes, click here.

Mandatory for all calculation types.

JOB CONTROL
fklist

Variable type: string
Default value: ''
Typical value: 'prefix_tet.kpt'

Name of the file containing the k-point list (in crystal coordiates).

Mandatory for calc_mode:  bands, ephmat, imsigma, meanfp

JOB CONTROL
fqlist

Variable type: string
Default value: ''
Typical value: 'prefix_phdisp.qpt'

Name of the file containing the q-point list (in crystal coordiates).

Mandatory for calc_mode:  phdisp, ephmat Optional for calc_mode:  imsigma

JOB CONTROL
ftemper

Variable type: string
Default value: ''
Typical value: 'prefix.temper'

Name of the file containing values for the temperature (K), chemical potential (eV), and carrier concentration (cm-2 or cm-3).

Mandatory for calc_mode:  setup, imsigma, meanfp, trans, trans-pp, dynamics-run, dynamics-pp

JOB CONTROL
debug

Variable type: logical
Default value: .false.

Debug mode.

Optional for calc_mode:  qe2pert

JOB CONTROL
yaml_fname

Variable type: string
Default value: '.yml'

Name of the YAML output file. If the parameter (yaml_fname) is not changed by the user, the output name of the YAML file will be {prefix}_{calc_mode}.yml. For example, for Si bands calculation, the YAML file would be called si_bands.yml.

Optional for all calculation types.

JOB CONTROL
hole

Variable type: logical
Default value: .false.

Set to .true. for calculations on hole carriers.

Optional for calc_mode:  setup, trans, trans-pp, dynamics-run, dynamics-pp

JOB CONTROL
tmp_dir

Variable type: string
Default value: '.'
Typical value: './tmp'

The directory where the e-ph matrix elements are stored when calc_mode='trans'.

Optional for calc_mode:  trans, dynamics-run

JOB CONTROL
load_scatter_eph

Variable type: logical
Default value: .false.

Read the e-ph matrix elements from the files in tmp_dir. Used for calc_mode='trans'.

Optional for calc_mode:  trans, dynamics-run

JOB CONTROL
find_efermi

Variable type: logical
Default value: .false.
Typical value: .false.

Flag to indicate whether to find the Fermi energy, which means fix the Fermi energy or occupancy.

Optional for calc_mode:  setup

JOB CONTROL
sampling

Variable type: string
Default value: 'uniform'
Options:
'uniform'
random sampling from an uniform distribution.
'cauchy'
random sampling from a Cauchy disrtibution.

Random q points sampling method.

Optional for calc_mode:  imsigma

JOB CONTROL
cauchy_scale

Variable type: real
Default value: 0.05
Typical value: 1.0

Scale parameter gamma for the Cauchy distribution; used when sampling='cauchy'.

Optional for calc_mode:  imsigma

JOB CONTROL
nsamples

Variable type: integer
Default value: 100000

Number of q-points for the summation over the q-points in imsigma calculation.

Optional for calc_mode:  imsigma

JOB CONTROL
use_mem

Variable type: logical
Default value: .true.
Typical value: .true.

Flag for using memory or not and only used in boltz_scatter




 Boltzmann Transport Equation

BOLTZMANN TRANSPORT EQUATION
boltz_kdim

Variable type: integer
Default value: (1,1,1)
Dimensions: (3)

Number of k points along each dimension for the Boltzmann equation.

Mandatory for calc_mode:  setup, trans, trans-pp, dynamics-run, dynamics-pp

BOLTZMANN TRANSPORT EQUATION
boltz_qdim

Variable type: integer
Default value: (0,0,0)
Dimensions: (3)

Number of q points along each dimension for the Boltzmann equation. It should be same with boltz_kdim.

Optional for calc_mode:  trans, dynamics-run

BOLTZMANN TRANSPORT EQUATION
band_min

Variable type: integer
Default value: 1

Lowest band included.

Optional for calc_mode:  ephmat, setup, imsigma, meanfp, trans, trans-pp, dynamics-run, 
dynamics-pp

BOLTZMANN TRANSPORT EQUATION
band_max

Variable type: integer
Default value: 9999999

Highest band included.

Optional for calc_mode:  ephmat, setup, imsigma, meanfp, trans, trans-pp, dynamics-run, 
dynamics-pp

BOLTZMANN TRANSPORT EQUATION
boltz_emin

Variable type: real
Default value: -9999.0
Units: eV

Bottom of the energy window for the Boltzmann equation.

Optional for calc_mode:  setup, trans, trans-pp, dynamics-run, dynamics-pp

BOLTZMANN TRANSPORT EQUATION
boltz_emax

Variable type: real
Default value: 9999.0
Units: eV

Top of the energy window for the Boltzmann equation.

Optional for calc_mode:  setup, trans, trans-pp, dynamics-run, dynamics-pp

BOLTZMANN TRANSPORT EQUATION
boltz_nstep

Variable type: integer
Default value: 0
Typical value: 50

Number of iterations for solving the Boltzmann transport equation.

Mandatory for calc_mode:  dynamics-run Optional for calc_mode:  trans

BOLTZMANN TRANSPORT EQUATION
boltz_de

Variable type: real
Default value: 1.0
Units: meV

Energy step for the integrals in the Boltzmann equation.

Optional for calc_mode:  trans, trans-pp, dynamics-pp

BOLTZMANN TRANSPORT EQUATION
delta_smear

Variable type: real
Default value: 10.0
Units: meV

Smearing for the Dirac delta function.

Optional for calc_mode:  imsigma, trans, dynamics-run

BOLTZMANN TRANSPORT EQUATION
full_ite

Variable type: logical
Default value: .true.

Solve BTE with both E- and T-fields iteratively.

Optional for calc_mode:  trans

BOLTZMANN TRANSPORT EQUATION
phfreq_cutoff

Variable type: real
Default value: 1.0
Typical value: 1.0
Units: meV

Phonon energy threshold. Phonons with energy smaller than phfreq_cutoff will be excluded.

Optional for calc_mode:  ephmat, imsigma, trans, dynamics-run

BOLTZMANN TRANSPORT EQUATION
trans_thr

Variable type: real
Default value: 0.002

Threshold for the iterative procedure.

Optional for calc_mode:  trans



 Polar correction

POLAR CORRECTION
polar_split

Variable type: string
Default value: ''
Options:
''
(leave blank) both the polar and nonpolar parts, no split
'polar'
polar part only
'rmpol'
remainder part

Polar correction mode.

Optional for calc_mode:  imsigma



 Ultra-fast dynamics

ULTRA-FAST DYNAMICS
time_step

Variable type: real
Default value: 1.0
Typical value: 1.0
Units: fs

Time step for the carrier dynamics.

Mandatory for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
output_nstep

Variable type: integer
Default value: 1

Print out the results every output_nstep time steps.

Mandatory for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
boltz_init_dist

Variable type: string
Default value: ''
Typical value: 'gaussian'
Options:
'restart'
restart from the previous calculations.
'lorentz'
Loretnzian distribution
'fermi'
Fermi-Dirac distribution
'gaussian'
Gaussian distribution

Initial electron distribution at time zero.

Mandatory for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
boltz_init_e0

Variable type: real
Default value: -9999.0
Typical value: 1.0
Units: eV

Energy parameter used to generate initial distribution. Needs to be specified for boltz_init_dist='lorentz' (center), 'gaussian' (center), or 'fermi' (chemical potential).

Optional for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
boltz_init_smear

Variable type: real
Default value: 20.0
Typical value: 1.0
Units: meV

The broadening or width of the initial distribution for boltz_init_dist='lorentz' or 'gaussian', or temperature (in meV) for 'fermi'.

Optional for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
solver

Variable type: string
Default value: 'rk4'
Options:
'euler'
Euler method (first-order)
'rk4'
fourth-order Runge-Kutta method

Solver type for the Boltzmann transport equation.

Optional for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
boltz_efield

Variable type: real
Default value: (0.0, 0.0, 0.0)
Dimensions: (3)
Units: V/cm

External electric field for the ultrafast real-time dynamics.

Optional for calc_mode:  dynamics-run, dynamics-pp

ULTRA-FAST DYNAMICS
boltz_norm_dist

Variable type: logical
Default value: .false.

Normalize the distribution function at each step of the real-time Boltzmann Transport Equation simulation.

Optional for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
boltz_acc_thr

Variable type: real
Default value: 0.0
Typical value: 1.0
Units: cm/s2

Drift acceleration threshold. If specified, the real-time simulation will stop when at least 10 last iterations had a drift acceleration lower than the threshold.

Optional for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
boltz_nstep_min

Variable type: integer
Default value: 1
Typical value: 100

Minimum number of iterations of real-time dynamics. Used with boltz_acc_thr. Will not be applied if boltz_acc_thr is not specified, in this case, use boltz_nstep instead.

Optional for calc_mode:  dynamics-run

ULTRA-FAST DYNAMICS
ph_mode_exclude_ranges

Variable type: integer
Default value: -1
Dimensions: (30, 2)

Specify the phonon modes to exclude in rt-BTE: the g2 factor will be set to zero for these modes. The modes to exclude are specified with ranges, e.g. to exclude modes from 2 to 5, write in the input file: ph_mode_exclude_ranges(1,:)=2,5 . To add another range to exclude, specify ph_mode_exclude_ranges(2,:)=7,10 . One can use up to 30 ranges. To exclude one mode, set first and second number to the phonon mode index. The indices of the phonon modes to exclude must be smaller than the total number of modes in a system.

Optional for calc_mode:  dynamics-run