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48 lines
1.8 KiB
Plaintext
48 lines
1.8 KiB
Plaintext
This example shows how to use the pwcond.x program to calculate
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the complex band structure of a system and its transmittance.
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The ballistic conductance is then given by the Landauer-Buttiker formula.
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In this example four systems are calculated:
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1) The complex band structure of Al bulk along the (001) direction.
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2) The complex band structure of a monatomic Al nanowire.
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3) The complex band structure of Ni bulk along the (001) direction.
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4) The transmittance of an Al wire without and with an H impurity.
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NB: In order to make the tests faster, these calculations are not fully
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converged with respect to k points, cut-off and size of the cell.
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The calculation proceeds in this way:
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1.a) A pw.x calculation provides the self-consistent potential of a two
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atom tetragonal Al(001) super-cell. Al is described by norm conserving
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pseudo-potentials.
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1.b) A pwcond.x calculation provides for every energy in the chosen
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region the values of the k vectors (in general complex) which
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correspond to those energies.
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2.a) A pw.x calculation provides the self-consistent potential of a
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monatomic Al wire, described by a unit cell with a single atom.
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2.b) A pwcond.x calculation provides the real and complex k vectors
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which correspond to those energies.
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3.a) A pw.x calculation provides the self-consistent potential of a two
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atom tetragonal Ni(001) super-cell. Ni is described by an ultrasoft
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pseudo-potential.
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3.b) A pwcond.x calculation provides the real and complex k vectors which
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correspond to those energies.
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4.a) A pw.x calculation provides the self-consistent potential of
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a perfect Al wire and of a wire (5 atoms long) with an H atom impurity.
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4.b) A pwcond.x calculation gives for every energy in the chosen region
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the transmittance at that energy for a perfect Al wire and for a wire
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with an H impurity.
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