Quantum-dot-layer-density
Special density model for layers of quantum dots: In dot layers the density of states depends first on the electronic
structure of the individual dots and second on the density and thickness of the layer.
This command should emulate a dot layer with dots of a certain energy distribution
due to a natural size fluctuation of the dots.
1D-only !!!
 The density is calculated by summing over all eigenstates with an
artificial line-broadening of gaussian shape. The line width sigmaj (cb-width-eigenvalues)has
to be provided by the user as well as the degeneracy alphaj (cb-degeneracy-eigenvalues).
To determine the charge density one also needs the density of quantum dots
within the layer NQD (sheet-density) and the thickness of the
layer dQD (sheet-width).
!-----------------------------------------------------------------!
$quantum-dot-layer-density
optional !
density-number
integer
required !
quantum-region
integer
optional !
model-active
character
optional !
use-bound-states
character
optional !
sheet-density
double
optional !
sheet-width
double
optional !
cb-set-number
integer
optional !
cb-number-of-eigenvalues
integer
optional !
cb-eigenvalues
double_array optional !
cb-width-eigenvalues
double_array optional !
cb-degeneracy-eigenvalues
integer_array optional !
cb-occupy-levels
integer_array optional !
vb-set-number
integer
optional !
vb-number-of-eigenvalues
integer
optional !
vb-eigenvalues
double_array optional !
vb-width-eigenvalues
double_array optional !
vb-degeneracy-eigenvalues
integer_array optional !
vb-occupy-levels
integer_array optional !
$end_quantum-dot-layer-density
optional !
!-----------------------------------------------------------------!
Synatx:
density-number = 1
Sequencial numbering for several dot layers
quantum-region = 1
A quantum dot layer is always located in a quantum region, therefore the number of this region has to specified.
model-active = yes / no
Flag whether this dot-layer-density is active or not.
use-bound-states = yes /
no
Flag whether to use quantum states from calculation or user specified ones.
use-bound-states = yes :
Bound states which are specified by the command
$quantum-bound-states are used for energy levels and density distribution in
the z-direction.
use-bound-states = no :
No calculated eigenvalues are used, but user specified eigenvalues.
sheet-density = 1d10 ! [1/cm^2]
Number of dots per cm² (typically 1*1010 -
1*1011, i.e. (1d10 -
1d11)
sheet-width = 5d0 ! [l0]
Width of dot-layer in units of [l0], i.e. [nm].
cb-set-number = 1
Number of electron bound states set specified by command
$quantum-bound-states used for eigenvalues and eigenfunctions only necessary if use-bound-states =
yes
cb-number-of-eigenvalues = 2
Number of eigenvalues for electrons in quantum dot.
cb-eigenvalues = 0.1d0 0.3d0 ! [eV]
Only if use-bound-states = no.
Energies of eigenstates have to provided in units of [eV].
cb-width-eigenvalues = 0.001d0 0.002d0
! [eV]
Due to size fluctuations of the quantum dots the eigenvalues have a gaussian line shape with a width provided by the user in units of [eV].
cb-degeneracy-eigenvalues = 2 4
Determines the degeneracy of the eigenvalues.
cb-occupy-levels = 1
= 0
= -1
Special cheat mode for occupation of levels:
1: level always occupied
0: level occupied with Fermi distribution and local quasi-Fermi level
-1: level always unoccupied
Same for valence band:
vb-...
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