EPW Forum

Hello teachers.
Please ask a please question, when using epw core to calculate superconducting properties, the lambda value appears to have a huge oscillation and does not converge what could be the cause? The fit of the energy band near the Fermi surface meets the requirements of the calculation, please guide me. My input file is attached below：
--
&inputepw

outdir='./tmp/',

ep_coupling = .true.
elph = .true.


epbwrite = .true.
epbread = .false.

epwwrite = .true.
epwread = .false.

etf_mem = 1,

nbndsub = 10,
!efermi_read=.true.,
!fermi_energy=0.6474,
bands_skipped = 'exclude_bands = 1-19'


wannierize = .true.
num_iter = 400
dis_win_max = 15
dis_froz_max= 2.0
dis_froz_min= -1.95
dis_win_min = -11.5
!dis_mix_ratio = 1.d0
proj(1) = 'Nb:d'
wdata(1) = 'bands_plot = .true.'
wdata(2) = 'begin kpoint_path'
wdata(3) = 'G 0.000000 0.000000 0.000000 M 0.333333 0.333333 0.000000'
wdata(4) = 'M 0.333333 0.333333 0.000000 K 0.500000 0.000000 0.000000'
wdata(5) = 'K 0.500000 0.000000 0.000000 G 0.000000 0.000000 0.000000'
wdata(6) = 'end kpoint_path'
wdata(7) = 'guiding_centres = .true.'
wdata(8) = 'bands_plot_format = gnuplot'


!filukk = 'aiida.ukk'

iverbosity = 2

!eps_acustic = 2.0 ! Lowest boundary for the
ephwrite = .true. ! Writes .ephmat files used when wliasberg = .true.

fsthick = 0.4 ! eV
nstemp = 9
temps = 0.3 0.9 1.5 2.1 2.7 3.3 3.9 4.2 4.4 ! K
degaussw = 0.1 ! eV
degaussq = 0.05 ! meV
nqstep = 1000

!eliashberg = .true.
!phonselfen=.true.
!a2f =.true.

!laniso = .true.
!liso = .true.
!limag = .true.
!lpade = .true.
!lacon = .true.

broyden_beta = 0.05
conv_thr_iaxis = 1.0d-5
conv_thr_racon = 1.0d-5

wscut = 0.5 ! eV Upper limit over frequency integration/summation in the Elisashberg eq

!max_memlt
!time_max = 82000

nsiter = 500

muc = 0.1

dvscf_dir = './save'

nk1 = 16
nk2 = 16
nk3 = 1

nq1 = 8
nq2 = 8
nq3 = 1

mp_mesh_k = .true.
nkf1 = 64
nkf2 = 64
nkf3 = 1

nqf1 = 64
nqf2 = 64
nqf3 = 1
/

Hi Zhou,

Can you share your plots comparing the spectral functions and lambdas for different convergence tests?

Happy EPWing,
Hari