Output-bandstructure
The output of potential, valence and conduction bands is controlled by this
keyword.
!-------------------------------------------------------------------!
$output-bandstructure
optional !
destination-directory
character
required !
conduction-band-numbers
integer_array
optional !
valence-band-numbers
integer_array
optional !
potential
character
optional !
built-in-potential
character
optional !
electric-field
character
optional !
output-grid-position
double_array
optional !
output-grid-position-octant
character
optional !
$end_output-bandstructure
optional !
!-------------------------------------------------------------------!
Syntax:
destination-directory
=
band_struc/
= /MOSFET/band_struc/
Name of directory to which the files should be written. Must exist
and directory name has to include the slash (\ for DOS and / for UNIX)
conduction-band-numbers = 1 2 3
Numbers of conduction band edges that are put out (1,
..., max_num_cbbands). The numbering corresponds
to the original numbering in the database. If a band is
splitted because of strain, there will be several columns in the output file
for all subbands.
1 = Gamma
band
2 = L band
3 = X band
If one does not want to print any conduction band, one can put this line
into comments or delete it.
valence-band-numbers = 1 2 3
Numbers of valence bands that are put out (1,
..., max_num_vbbands).
1 = heavy hole band
2 = light hole band
3 = split-off hole band
If one does not want to print any valence band, one can put this line into
comments or delete it.
potential = yes
=
no
Flag whether to put out the electrostatic potential in units of [V].
The electrostatic potential is the solution of the Poisson equation.
built-in-potential = yes
=
no
Flag whether to put out the electrostatic built-in potential in units of [V].
Two built-in potentials are written out:
The electrostatic
built-in potential is the solution of the Poisson equation in equilibrium.
The classical electrostatic built-in potential is the solution of the Poisson equation
in equilibrium using only classical densities, i.e. ignoring any quantum
mechanical densities. (This potential is used as a start value for the
quantum mechanical calculations.)
==> potential_built_in_cl_1D.dat
==> potential_built_in_1D.dat
electric-field = yes
=
no
Flag whether to put out the electric field in the file
electric_field.fld.
The electric field can be visualized with
AVS/Express in 2D/3D.
New: Electric field output has been
implemented.
Units: V/m
output-grid-position =
10d0 !
[nm] 1D: x = 10 nm
= 10d0 20d0 !
[nm] 2D: (x,y) = (10 nm, 20 nm)
= 10d0 20d0 0d0 ! [nm]
3D: (x,y,z) = (10 nm, 20 nm, 0 nm)
Here, one can specify a grid point (i,j,k) where output like band edges,
potential, densities, ... are written out.
This also works together with a sweep (e.g. voltage sweep, magnetic field
sweep).
output-grid-position-octant = left !
1D: octant 1, i-
(default for 1D)
= right !
1D: octant 2, i+
= lowerleft
! 2D: octant 1, (i-,j-)
= lowerright
! 2D: octant 2, (i+,j-)
= upperleft
! 2D: octant 3, (i-,j+)
= upperright
! 2D: octant 4, (i+,j+)
= bottomlowerleft ! 3D: octant 1,
(i-,j-,k-)
= bottomlowerright ! 3D: octant 2, (i+,j-,k-)
= bottomupperleft ! 3D: octant 3,
(i-,j+,k-)
= bottomupperright ! 3D: octant 4, (i+,j+,k-)
= toplowerleft !
3D: octant 5, (i-,j-,k+)
= toplowerright ! 3D:
octant 6, (i+,j-,k+)
= topupperleft !
3D: octant 7, (i-,j+,k+)
= topupperright ! 3D:
octant 8, (i+,j+,k+)
output-grid-position,
then one has to specify for which octant the output should refer to.
(In 3D there are 8 octants, in 2D there are four "octants", and in 1D there are
two "octants".
Output
Band-edges:
Filename:
cb1D_001_ind000.dat |
cb
vb |
|
|
indicates if conduction (cb)
or valence (vb) band is contained |
| |
_001 |
|
number of band (for meaning of numbering,
see above) |
| |
|
_ind000 |
number of voltage step corresponding to
this output file (only if voltage sweep is turned on) |
Structure:
distance: |
sub_1: |
sub_2: |
0.000000E+00 |
0.000000E+00 |
0.000000E+00 |
| Position in space [l0] |
Subband 1 [eV] |
Subband 2 [eV] |
Remark:
Due to strain the bands with degenerate minima split into several subbands.
These subbands are listed in different columns (e.g. in silicon for the X band
(band no. 3) if strain is present, the band edges split.).
Potential:
Filename:
potential1D_ind001.dat |
| |
_ind000 |
number of voltage step corresponding to
this output file (only if voltage sweep is turned on) |
Structure:
distance: |
pot: |
0.000000E+00 |
0.000000E+00 |
| position in space [nm] |
electrostatic potential [V] |
Classical built-in potential for the device
First, the Poisson equation is solved in equilibrium, using on
classical densities, i.e. without quantum mechanics.
The resulting electrostatic potential is called the built-in potential of the
device for a classical density.
==> potential_built_in_cl_1D.dat
Built-in potential for the device
Then, the Poisson equation is solved again in equilibrium, using
either classical or quantum mechanical densities, or a combination of both,
depending on the input file).
The resulting electrostatic potential is called the built-in potential of the
device.
In case, no quantum mechanical densities are involved, the built-in potential is
identical to the classical built-in potential.
==> potential_built_in_1D.dat
| 
