Dear PWSCF users and developers, I have tried to do a transmission calcuation and not getting right results. I have tried to figure out the reason behind this and realized that in my set up for some reason the Bloch waves in left lead get changed resulting wrong transmission. By this I meant that, if I just try to calculate complex band of the left lead, I have a kz for each kx,ky and E but when I am doing transmission calculation, the Bloch's wave in the same lead has different kz for the same kx,ky and E, which does not make sense as why should the Bloch's wave in lead get affected by the presence of scattering region? For the right lead kz remains the same in both cases though, which I believe how it should be. I did this for several cases, I interchanged right and left leads, increased number of atoms in the scattering region, chose scattering region in different way, and everytime kz of left lead changes. Following is my input file for the scattering region -
scf part - &control calculation='scf' pseudo_dir = '/home/manoj/espresso-4.0.1/pseudo', outdir='./', prefix='cus', / &system ibrav =0, celldm(1)=4.82, nat= 10, ntyp= 1, ecutwfc =50.0, occupations='smearing', smearing='gaussian', degauss=0.02, ecutrho=500 / &electrons conv_thr = 1.0e-8 mixing_beta=0.7 / ATOMIC_SPECIES Cu 63.55 Cu.pz-d-rrkjus.UPF ATOMIC_POSITIONS Cu 0.0 0.0 0.0 Cu -0.5 0.288675134 0.816496581 Cu -1.0 0.577350269 1.632993162 Cu -1.5 0.866025404 2.449489743 Cu 0.0 0.0 3.265986324 Cu 0.5 -0.288675134 4.082482905 Cu 1.0 -0.577350269 4.898979486 Cu 1.5 -0.866025404 5.715476066 Cu 1.0 -0.577350269 6.531972647 Cu 0.5 -0.288675134 7.348469228 K_POINTS (automatic) 6 6 4 1 1 1 CELL_PARAMETERS {hexagonal} 1.0 0.0 0.0 -0.5 0.866025403 0.0 0.0 0.0 8.16496581 conductance part - &inputcond outdir='./' prefixl='cul' prefixr='cur' prefixs='cus' tran_file ='trans.twin' ikind=2 ecut2d=50 energy0=0.0 denergy=0.0 ewind=5.d0 epsproj=1.d-6 nz1=25 / 2 0.000000 0.000000 1 0.5000000 -0.5000000 1 1 0.0 Thank you for your attention. Regards, Manoj Srivastava Graduate Student Department of Physics University of Florida, Gainesville, FL