I-V curve dependence of device length along transport direction
Hi,
I am using the Transiesta and TbTrans to calculate the I-V curve under the finite voltage (0-2 eV), normally I run the Transiesta calculations first and followed by the TbTrans code for each applied voltage. But the results show that if I change the length of the devices along the transport directions, it will significantly affect the values of current (36.5 Angstrom of the length corresponds to 1.05*10^-10 A, 54.7 Angstrom to 1.46*10^-6 A). I am wondering why there will be such a huge variations? Is it normal?
Below is my input files for Electrodes and Transport calculations:
Thanks for your kindness.
Elec:
SystemName elec
SystemLabel elec
# -------
# Lattice
# -------
LatticeConstant 1.00 Ang
%block LatticeVectors
24.323716 -0.131002 -0.182012
0.000000 9.934577 0.000000
0.000000 0.000468 9.082148
%endblock LatticeVectors
# -------
# Species and Atoms
# -------
NumberOfSpecies 1
NumberOfAtoms 24
%block ChemicalSpecies
1 15 P
%endblock ChemicalSpecies
%block PAO.BasisSizes
P DZP
%endblock PAO.BasisSizes
# -------
# Exchange-
# -------
XC.functional GGA
XC.authors PBE
# -------
# Atomic Coordinates
# -------
AtomicCoordinat
%block AtomicCoordinat
9.0008696 4.0865698 0.2964436 1
8.9926968 0.773647 0.299635 1
8.993913 7.3984385 0.3001742 1
8.9983399 2.4317411 1.7799078 1
8.9992399 5.7410405 1.779924 1
8.9992885 9.0527092 1.7837393 1
11.1027792 5.7419701 2.5831458 1
11.1019765 2.4297956 2.5833803 1
11.1028765 9.0531747 2.5841275 1
11.1006874 4.0860958 4.0660813 1
11.1009549 7.3975081 4.0664905 1
11.0987658 0.7745301 4.0665069 1
8.995494 7.39688 4.8638732 1
8.9935238 0.7747817 4.8648705 1
8.9952995 4.08658 4.86504 1
8.991432 9.0531023 6.3457953 1
8.9935968 5.7423956 6.3477897 1
8.9925022 2.4309645 6.3478893 1
11.0942416 9.0524364 7.1508733 1
11.0954578 2.4311091 7.1521208 1
11.0961388 5.7418007 7.1529154 1
11.0932443 0.7743777 8.633275 1
11.0926119 7.3980433 8.6344908 1
11.0950443 4.0861296 8.6353408 1
%endblock AtomicCoordinat
# -------
# Calculation Details
# -------
%block kgrid_Monkhorst
1 0 0 0.0
0 3 0 0.0
0 0 60 0.0
%endblock kgrid_Monkhorst
MeshCutoff 150.0 Ry
MaxSCFIterations 500
DM.MixingWeight 0.2
DM.NumberPulay 5
DM.Tolerance 1.d-4
WriteCoorXmol .true.
Diag.DivideAndC
ElectronicTempe
OccupationFunction FD
SolutionMethod diagon
TS.WriteHS .true.
# -------
# Parallelized Running
# -------
BLOCKSIZE 8
Diag.Memory 1.3
Transiesta and TbTrans:
SystemName scat
SystemLabel scat
# -------
# Lattice
# -------
LatticeConstant 1.00 Ang
%block LatticeVectors
24.323716 -0.131002 -0.182012
0.000000 9.932301 0.000000
0.000000 0.001880 36.523614
%endblock LatticeVectors
# -------
# Species and Atoms
# -------
NumberOfSpecies 3
NumberOfAtoms 116
%block ChemicalSpecies
1 1 H
2 6 C
3 15 P
%endblock ChemicalSpecies
%block PAO.BasisSizes
H DZP
C DZP
P DZP
%endblock PAO.BasisSizes
# -------
# Exchange-
# -------
XC.functional GGA
XC.authors PBE
# -------
# Atomic Coordinates
# -------
AtomicCoordinat
%block AtomicCoordinat
9.0008696 4.071713 0.2883808 3
8.9926968 0.7587903 0.2915722 3
8.993913 7.3835817 0.2921115 3
8.9983399 2.4168843 1.7718451 3
8.9992399 5.7261837 1.7718612 3
8.9992885 9.0378524 1.7756766 3
11.1027792 5.7271133 2.575083 3
11.1019765 2.4149389 2.5753175 3
11.1028765 9.038318 2.5760648 3
11.1006874 4.0712391 4.0580185 3
11.1009549 7.3826514 4.0584278 3
11.0987658 0.7596734 4.0584442 3
8.995494 7.3820232 4.8558105 3
8.9935238 0.759925 4.8568077 3
8.9952995 4.0717233 4.8569772 3
8.991432 9.0382455 6.3377325 3
8.9935968 5.7275388 6.339727 3
8.9925022 2.4161078 6.3398266 3
11.0942416 9.0375796 7.1428105 3
11.0954578 2.4162524 7.1440581 3
11.0961388 5.7269439 7.1448527 3
11.0932443 0.759521 8.6252123 3
11.0926119 7.3831865 8.626428 3
11.0950443 4.0712729 8.6272781 3
8.9894861 0.7595561 9.4271291 3
8.9911158 4.0720739 9.4286478 3
8.988951 7.3824562 9.4295551 3
8.9920401 2.4154183 10.90955 3
8.9933779 5.7274509 10.9117563 3
8.991359 9.0382728 10.9120913 3
11.0967956 9.0373606 11.711209 3
11.0958226 2.4177143 11.7130671 3
11.0975982 5.7250154 11.7137849 3
11.0945091 0.7617199 13.1949685 3
11.0961145 7.3818961 13.1954363 3
11.0873093 4.0709472 13.198701 3
15.4151552 4.0590903 13.621666 1
8.9882699 7.3838536 13.9872161 3
8.9869078 0.7590398 13.9879803 3
8.9780783 4.0722862 13.9900114 3
14.0924072 3.1594682 14.406954 1
14.0758914 4.9326082 14.4082201 1
14.7337019 4.0520717 14.4854613 2
8.9852294 9.0385869 15.47057 3
8.976108 5.7294245 15.4711409 3
8.9750135 2.4148872 15.4712176 3
15.4950829 4.0586567 15.8121801 2
16.1467882 4.9475171 15.8667783 1
16.1623068 3.1814065 15.8671649 1
11.0876985 9.035767 16.2770215 3
11.0765582 2.4218084 16.2775161 3
11.0775555 5.7222289 16.2780113 3
13.8864583 4.9274079 16.9568452 1
13.9027552 3.1624059 16.959328 1
14.558182 4.051061 17.0185595 2
11.0870904 0.7642434 17.7584835 3
11.0862877 7.3793559 17.7594263 3
11.0570263 4.0718092 17.7683506 3
15.2716209 4.0599686 18.3688512 2
15.9210155 4.9512297 18.4349825 1
15.9414961 3.1839796 18.4354233 1
8.9526357 4.0716156 18.5640802 3
8.9844268 0.7588948 18.5649619 3
8.9832835 7.3832817 18.565793 3
13.6479156 3.1619836 19.470194 1
13.6285539 4.9209983 19.4710015 1
14.300983 4.0487283 19.5495728 2
8.973627 2.4147825 20.0473228 3
8.9881483 9.0401282 20.0479681 3
8.9732865 5.7281454 20.048582 3
11.0834418 5.7280652 20.8401244 3
11.0833932 2.4155389 20.8403761 3
11.0923443 9.0389446 20.8486945 3
14.9972981 4.0564537 20.9090864 2
15.6477386 3.1750778 21.0236488 1
15.6266256 4.9530179 21.0240353 1
14.2696784 4.0478968 21.7360296 1
11.1016603 4.0720815 22.3228393 3
11.0934146 7.3803409 22.3275621 3
11.0930011 0.7641455 22.3285934 3
9.0008696 4.0728894 23.1369808 3
8.9926968 0.7599667 23.1401722 3
8.993913 7.3847581 23.1407115 3
8.9983399 2.4180607 24.6204451 3
8.9992399 5.7273601 24.6204612 3
8.9992885 9.0390288 24.6242765 3
11.1027792 5.7282897 25.423683 3
11.1019765 2.4161153 25.4239175 3
11.1028765 9.0394944 25.4246648 3
11.1006874 4.0724155 26.9066185 3
11.1009549 7.3838278 26.9070278 3
11.0987658 0.7608498 26.9070441 3
8.995494 7.3831996 27.7044105 3
8.9935238 0.7611014 27.7054077 3
8.9952995 4.0728997 27.7055772 3
8.991432 9.039422 29.1863325 3
8.9935968 5.7287152 29.188327 3
8.9925022 2.4172842 29.1884266 3
11.0942416 9.038756 29.9914105 3
11.0954578 2.4174288 29.9926581 3
11.0961388 5.7281203 29.9934527 3
11.0932443 0.7606974 31.4738123 3
11.0926119 7.3843629 31.475028 3
11.0950443 4.0724493 31.475878 3
8.9894861 0.7607325 32.2757291 3
8.9911158 4.0732503 32.2772478 3
8.988951 7.3836326 32.2781551 3
8.9920401 2.4165947 33.75815 3
8.9933779 5.7286273 33.7603563 3
8.991359 9.0394492 33.7606913 3
11.0967956 9.0385371 34.559809 3
11.0958226 2.4188907 34.561667 3
11.0975982 5.7261918 34.5623849 3
11.0945091 0.7628963 36.0435685 3
11.0961145 7.3830725 36.0440363 3
11.0873093 4.0721236 36.047301 3
%endblock AtomicCoordinat
# -------
# Calculation Details
# -------
%block kgrid_Monkhorst
1 0 0 0.0
0 3 0 0.0
0 0 1 0.0
%endblock kgrid_Monkhorst
MeshCutoff 150.0 Ry
MaxSCFIterations 500
DM.MixingWeight 0.2
DM.NumberPulay 5
DM.Tolerance 1.d-4
WriteCoorXmol .true.
Diag.DivideAndC
DM.UseSaveDM .true.
ElectronicTempe
OccupationFunction FD
SolutionMethod transiesta
TS.WriteHS .true.
# Left Electrode
TS.HSFileLeft ../Elec/elec.TSHS
TS.ReplicateA1Left 1
TS.ReplicateA2Left 1
TS.NumUsedAtomsLeft 24
TS.BufferAtomsLeft 0
# Right Electrode
TS.HSFileRight ../Elec/elec.TSHS
TS.ReplicateA1Right 1
TS.ReplicateA2Right 1
TS.NumUsedAtoms
TS.BufferAtomsRight 0
%block TBT_kgrid_
1 0 0 0.0
0 10 0 0.0
0 0 1 0.0
%endblock TBT_kgrid_
TS.Voltage 2.0 eV
TS.BiasContour.Eta 0.001 Ry
TS.BiasContour.
TS.TBT.HSFile './scat.TSHS'
TS.TBT.Emin -2.0 eV
TS.TBT.Emax 2.0 eV
TS.TBT.NPoints 101
# -------
# Parallelized Running
# -------
BLOCKSIZE 8
Diag.Memory 1.3
Question information
- Language:
- English Edit question
- Status:
- Solved
- For:
- Siesta Edit question
- Assignee:
- No assignee Edit question
- Solved by:
- Nick Papior
- Solved:
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