Simple examples

Here we present some simple (and not very) examples of how to use pwcond.x program to calculate either the complex band structure (CBS) of the lead or to solve the scattering problem and to find transmission and reflection coefficients.
The calculations proceed in two steps:
1) you run pw.x with a given input file to calculate the self-consistent potential;
2) you run pwcond.x with a given input file to solve the CBS or the scattering problem.

  • Complex bands of infinite monatomic Al wire
  • - run pw.x with lead.in input file.
    - run pwcond.x with cond.in input file.

  • Complex bands of ferromagnetic fcc Ni along [001] direction
  • - run pw.x with lead.in input file (tetragonal unit cell with 2 atoms per cell is used).
    - run pwcond.x with cond_up.in or cond_down.in input files for up or down spin channels.

  • Perfect monatomic Al wire without any scatterer (a test case)
  • - run pw.x with lead.in input file.
    - run pwcond.x with cond.in input file.

  • Monatomic Al wire with an H adatom as a scatterer
  • CNT(4x4)+Co
    - run pw.x with lead.in input file.
    - run pw.x with scat.in input file.
    - run pwcond.x with cond.in input file.

  • Monatomic Ni wire with a spin reversal
  • CNT(4x4)+Co
    - run pw.x with lead_up.in and lead_down.in input files for the wires magnetized in opposite directions.
    - run pw.x with scat.in input file.
    - run pwcond.x with cond_up.in or cond_down.in input files for up or down spin channels.

    More realistic (and time-consuming) examples

  • Single-walled carbon nanotube (4x4) with a Co impurity
  • CNT(4x4)+Co
    - run pw.x with lead.in input file.
    - run pw.x with scat.in input file.
    - run pwcond.x with cond.in input file.

  • Platinum nanowire contact
  • CNT(4x4)+Co
    - run pw.x with lead.in input file.
    - run pw.x with scat.in input file.
    - run pwcond.x with cond.in input file.

  • Planar interface: Magnetic Tunnel Junction
  • CNT(4x4)+Co
    PARALLEL magnetic configuration of the left and right leads:
    - run pw.x with lead.in input file.
    - run pw.x with scat.in input file.
    - run pwcond.x with cond_up.in or cond_down.in input files for up or down spin channels.
    ANTIPARALLEL magnetic configuration of the left and right leads:
    - run pw.x with lead_up.in and lead_down.in input files for the leads magnetized in opposite directions.
    - run pw.x with scat.in input file.
    - run pwcond.x with cond_up.in or cond_down.in input files for up or down spin channels.