$default-materials

Default materials.

$default-materials                          required
 material-name                character     required
 material-type                character     required
 material-model               character     required
 material-property            character     optional
$end_default-materials                      required

Explanation of specifiers.

material-name
type:

character

presence:

required

value:

e.g. Si

An arbitrary name can be chosen, e.g. Si or silicon.

material-type
type:

character

presence:

required

value:

e.g. Si-zb-default

The material parameters of Si-zb-default have to be defined in the database.

material-model
type:

character

presence:

required

value:

binary-zb-default, binary-wz-default, ternary-zb-default, ternary-wz-default; not supported yet: quaternary-wz-default

Zinc blende (zb) and wurtzite (wz) binary and ternary alloys are supported. Materials with diamond crystal structure can be specified using zinc blende. SiGe alloys are called “ternaries” even if only two atoms are involved.

For alloys (ternaries) only.

material-property
type:

character

presence:

optional

value:

swap-(x)-and-(1-x)

If material is a ternary material, this value can be set to swap-(x)-and-(1-x). This allows to specify 2 different types of SiGe alloys that contain the same material parameters but \(x\) and \(y=(1-x)\) are interchanged.

material-name = Si(1-x)Ge(x)    material-type = Si(1-x)Ge(x)-zb-default    material-model = ternary-zb-default
material-name = Si(x)Ge(1-x)    material-type = Si(1-x)Ge(x)-zb-default    material-model = ternary-zb-default   material-property = swap-(x)-and-(1-x)

Here, material-name is swapped but both refer to the same material-type.

You can also define your own materials, e.g. GaAs with parameters for 4 K, or explicit parameters for a ternary, e.g. Al(x)In(1-x)P with a fixed value of x=0.52: Al0.52In 0.48P

material-name  = GaAs-4K
material-model = binary-zb-default
material-type  = GaAs-4K-zb-default

material-name  = Al0.52In0.48P
material-model = binary-zb-default
material-type  = Al0.52In0.48P-zb-default

Further examples

!---------------------------------------------------------------!
$default-materials

 material-name  = Si
 material-type  = Si-zb-default
 material-model = binary-zb-default

 !------------------------------------------------------------------------------------------------------------------
 ! 'alias' materials: Here, we specify 4 different types of AlGaAs alloy that contain the same material parameters.
 !------------------------------------------------------------------------------------------------------------------
 material-name = Al(x)Ga(1-x)As    material-type = Al(x)Ga(1-x)As-zb-default    material-model = ternary-zb-default
 material-name = Ga(1-x)Al(x)As    material-type = Al(x)Ga(1-x)As-zb-default    material-model = ternary-zb-default
 material-name = Al(1-x)Ga(x)As    material-type = Al(x)Ga(1-x)As-zb-default    material-model = ternary-zb-default   material-property = swap-(x)-and-(1-x)
 material-name = Ga(x)Al(1-x)As    material-type = Al(x)Ga(1-x)As-zb-default    material-model = ternary-zb-default   material-property = swap-(x)-and-(1-x)

 material-name = Al(x)Ga(1-x)N
 material-type = Al(x)Ga(1-x)N-wz-default
 material-model = ternary-wz-default

$end_default-materials
!---------------------------------------------------------------!