## Solve anisotropic Eliashberg equations on imaginary-axis

Discussion around superconductivity

Moderator: stiwari

dhw
Posts: 17
Joined: Thu Dec 03, 2020 7:46 am
Affiliation: none

### Solve anisotropic Eliashberg equations on imaginary-axis

Hello everyone:
When I calculate the superconducting gap, that's where the computation stops shown below:
temp( 1) = 2.00000 K

Solve anisotropic Eliashberg equations on imaginary-axis

Total number of frequency points nsiw( 1) = 923
Cutoff frequency wscut = 1.0000

Size of allocated memory per pool: ~= -14.4842 Gb
Is there any way to solve my problem without adding compute nodes?
Here is my input file:
&inputepw
prefix = ''
outdir = './outdir/'
ep_coupling = .true.
elph = .false.
kmaps = .true.
epwwrite = .false.
wannierize = .false.
! num_iter = 0
dis_froz_min= 2.3
dis_froz_max= 8.3
proj(1) = ''
wdata(1) = 'Begin Kpoint_Path'
wdata(2) = 'G 0.00 0.00 0.00 M 0.00 0.50 0.00'
wdata(3) = 'M 0.00 0.50 0.00 K 0.333 0.333 0.00'
wdata(4) = 'K 0.333 0.333 0.0 G 0.00 0.00 0.00'
wdata(5) = 'End Kpoint_Path'
wdata(6) = 'bands_plot = .true.'
wdata(7) = 'bands_num_points = 55'
wdata(8) = 'guiding_centres = .true.'
wdata(9) = 'dis_num_iter = 5000'
bands_skipped = 'exclude_bands = 1:25'

system_2d=.true.
etf_mem = 1
nbndsub = 24,
iverbosity = 2
eps_acustic = 2.0 ! Lowest boundary for the phonon frequency
ephwrite = .false. ! Writes .ephmat files used when Eliasberg = .true.
fsthick = 0.32 ! eV
degaussw = 0.01 ! eV
nsmear = 1
nqsmear = 1
delta_smear = 0.01 ! eV
degaussq = 0.5 ! meV
nqstep = 500
eliashberg = .true.
laniso = .true.
limag = .true.
conv_thr_iaxis = 1.0d-4
max_memlt = 5.00d0
! asr_typ = 'crystal'
delta_approx = .true.,
! elecselfen = .true.,
phonselfen = .true.,
a2f = .false. ,
wscut = 1.0 ! eV Upper limit over frequency integration/summation in the Elisashberg eq
nstemp = 12 ! Nr. of temps
temps = 2.00 13.00 ! K provide list of temperetures OR (nstemp and temps = tempsmin tempsmax for even space mode)
nsiter = 500
muc = 0.21246
dvscf_dir = '../../phonon/save'

nk1 = 12
nk2 = 12
nk3 = 1
nq1 = 6
nq2 = 6
nq3 = 1

! mp_mesh_k = .true.
nkf1 = 60
nkf2 = 60
nkf3 = 1
nqf1 = 60
nqf2 = 60
nqf3 = 1
/

hlee
Posts: 415
Joined: Thu Aug 03, 2017 12:24 pm
Affiliation: The University of Texas at Austin

### Re: Solve anisotropic Eliashberg equations on imaginary-axis

Dear dhw:
Size of allocated memory per pool: ~= -14.4842 Gb
I think that you are using the computational parameters such that they result in the integer overflow. For example, the number of frequency points, nsiw( 1) (=923), is large.
Is there any way to solve my problem without adding compute nodes?
Basically, no. But you can try to uncomment the line of "! mp_mesh_k = .true." if there is no specific reason for commenting this line.

Sincerely,

H. Lee