Fw : Re: Re : Problem in calculation of V.B.

[h.h...@yahoo.fr]

Hi all,
sorry forget to forward.
best regards
hamza

--- En date de : Jeu 12.10.17, ms.kojima <ms.k...@takanori.jp.net a écrit :

De: ms.kojima <ms.k...@takanori.jp.net
Objet: Re: Re : Problem in calculation of V.B.
À: h.h...@yahoo.fr
Date: Jeudi 12 octobre 2017, 18h43
Dear Hamza,

Thank you for showing me the code for
supporting quaternary alloys.
I'm
entirely new to Python and it might be a bit tough, but
I'll try introducing it.

Regards,
Takanori Kojima

On
2017-10-04 09:50, h.h...@yahoo.fr
wrote:
Hi,
I am
glad you are using Aestimo, using quaternary alloy
InGaAsP
require some modification to
the code because our base included

ternary alloys that require only a parameter x to change
(example
GaAs+InAs=InxGa1-xAs) while in
quaternary we have x and y which need

to be included in the code according to interpolated
Vegard’s law for
quaternary.

Example of
modification in Aestimo_h.py
starting
from line 266:

 
          elif matType in alloy_property:
                alloyprops =
alloy_property[matType]
         
      mat1 =
material_property[alloyprops['Material1']]
                mat2 =
material_property[alloyprops['Material2']]
                # we add those two
line
                mat3 =
material_property[alloyprops['Material3']]
                mat4 =
material_property[alloyprops['Material4']]
                x = layer[2]
#alloy ratio x
               
#add a variable for "y" ratio
                # we put layer[6]
to prevent biger changes, as you see
in
structure file the "x" in third colone we put
layer[2]
                #put
the value of "y" in the saventh colone
                y= layer[6]
                #cb_meff_alloy =
x*mat1['m_e'] + (1-x)* mat2['m_e']
will be changed accourding to interpolated
Vegard’s law for quaternary

AxB1−xCyD1−y
               
cb_meff_alloy_ABC_x=x*mat1['m_e'] + (1-x)*
mat2['m_e']
             
  cb_meff_alloy_ABD_x=x*mat1['m_e'] + (1-x)*
mat3['m_e']
             
  cb_meff_alloy_ACD_y=y*mat4['m_e'] + (1-y)*
mat3['m_e']
             
  cb_meff_alloy_BCD_y=y*mat2['m_e'] + (1-y)*
mat3['m_e']
             
  cb_meff_alloy = (x*(1 − x)*(y*cb_meff_alloy_ABC_x +
(1
− y)*cb_meff_alloy_ABD_x)+ y*(1
− y)*(x*cb_meff_alloy_ACD_y + (1 −
               
x)*cb_meff_alloy_BCD_y))/(x*(1 − x) + y*(1 − y))#
define cb_meff_alloy_ABC_x same as
cb_meff_alloy
                #
all this just to obtain the new cb_meff_alloy, the
you repeate the same for the rest: C11,
.......................a0

as you can see it is too complicated and
needs more testing.

best regards
hamza

Ps: it will be
included in next release.

--------------------------------------------
En date de : Mar 3.10.17, ms.kojima
<ms.k...@takanori.jp.net
a
écrit :

  Objet: Problem in calculation of V.B.
  À: aestim...@googlegroups.com
  Date: Mardi 3 octobre 2017, 15h06

  Hi,

  I'm trying
Aestimo for calculating
 
characteristics of my InP-based
 
devices.
  The samples seem to work
fine on my
  environment(Visual Studio
with its
  Python support).
  However, when I introduced InGaAsP in
  my structure (single QW for
  practice) and included valence band
in
  the calculation,
  the energy level diagram and
  eigenstates of electrons and holes
went
  crazy (the QW looked like
type-II,
  energy came inside
  the bandgap etc...). When I
calculated
  with the same parameters,
but
  conduction band only, it looks
nice.
  As Aestimo doesn't
support
  III-III'-V-V' alloys,
I put material
  properties of InGaAsP
as a completely
  new material
  in database.py, based on some papers.
  Is there any other thing I have to
take
  care?

  Thanks in advance.