Creates a struct with material parameters for use with mqwgain and mqwindex commands.
Syntax 
Description 

result = buildmqwmaterial(location, T, matname, x); 
Ternary materials. location: string specifying the path to the database file. Alternatively, if empty struct, the default database will be used. T: temperature. matname: ternary material name. x: material composition. result: struct with material properties. 
result = buildmqwmaterial(location, 300, matname, x, cbValley); 
same as above with the additional parameter cbValley that specifies which conduction band valleys will be included for the interpolation of parameters. Possible values: “Gamma”, “X”, “L”, or “All” (default is “Gamma”; option “All” uses the lowest band gap to select). 
result = buildmqwmaterial(location, 300, matname, x, y); 
Quaternary material with compositions x and y. 
result = buildmqwmaterial(location, 300, matname, x, y, cbValley); 
Quaternary material with compositions x and y and the valley mixing specifier. 
The supported materials are listed in the table below:
IIIV semiconductors 
Ternary alloys 
Quaternary Alloys 

AlAs 
Al_{x}Ga_{1x}As 
In_{x}Ga_{1x}As_{y}P_{1y} 
GaAs 
Al_{x}Ga_{1x}P 
Al_{x}Ga_{y}In_{1xy}As 
InAs 
Al_{x}In_{1x}P 

AlP 
GaAs_{x}P_{1x} 

GaP 
In_{x}Al_{1x}As 

InP 
InAs_{x}P_{1x} 

In_{x}Ga_{1x}As 

In_{x}Ga_{1x}P 
When database materials are used, the properties of ternary alloys P(A_{x}B_{1−x}D) are interpolated from the corresponding properties of the base materials (P(AD) and P(BD)) according to the formula
$$ P\left(A_x B_{1x}D\right)=xP\left(AD\right)+\left(1x\right)P\left(BD\right)+x\left(1x\right)C, $$
where x is the composition fraction and C is the bowing parameter (quadratic coefficient).
Quaternary alloys of type A_{x}B_{1x}C_{y}D_{1y} (two group III and two group V elements) are composed from the interpolation of ternary alloy constituents [1]:
$$ P\left(A_xB_{1x}C_yD_{1y}\right)=\frac{x\left(1x\right)\left[\left(1y\right)P\left(A_xB_{1x}D\right)+yP\left(A_xB_{1x}C\right)\right]+y\left(1y\right)\left[xP\left(AC_yD_{1y}\right)+\left(1x\right)P\left(BC_yD_{1y}\right)\right]}{x\left(1x\right)+y\left(1y\right)}, $$
for composition fractions x and y. For example, a combination of the properties of In_{x}Ga_{1−x}P, In_{x}Ga_{1−x}As, InAs_{y}P_{1−y}, and GaAs_{y}P_{1−y} is used to define the properties of In_{x}Ga_{1−x}As_{y}P_{1−y}.
Quaternary alloys of type A_{x}B_{y}C_{1xy}D (three group III elements and one group V element) are composed from the interpolation of ternary alloy constituents [1]:
$$ P\left(A_xB_yC_{1xy}D\right)=\frac{xyP\left(A_{1u}B_uD\right)+y(1xy)P\left(B_{1v}C_{v}D\right)+x(1xy)P\left(A_{1w}C_{w}D\right)}{xy+y(1xy)+x(1xy)}, $$
for composition fractions x and y and u = (1x+y)/2, v = (2x2y)/2, w = (22xy)/2. For example, a combination of the properties of Al_{1u}Ga_{u}As, Ga_{1v}In_{v}As, and Al_{1w}In_{w}As, is used to define the properties of Al_{x}Ga_{y}In_{1xy}As.
result is a struct with the following fields:
Coefficient 
Units 
Description 

eg 
eV 
Band gap 
ep 
eV 
Energy parameter for the optical matrix element 
me 
1/m0 
Electron effective mass 
gamma1 
Luttinger parameter 

gamma2 
Luttinger parameter 

gamma3 
Luttinger parameter 

ac 
eV 
Conduction band deformation potential 
av 
eV 
Valence band deformation potential 
b 
eV 
Valence band deformation potential 
c11 
N/m2 
Elastic stiffness coefficient 
c12 
N/m2 
Elastic stiffness coefficient 
lc 
m 
Lattice constant 
vb 
eV 
Valence band absolute energy (all layers should have common reference) 
eps 

Relative static permittivity 
References
[1] Vurgaftman et al., J. Appl. Phys., 89, 5815 (2001)
Example
mymat = buildmqwmaterial(“/home/auser/myfolder/my_material_db.json”, 300, “InAlAs”, 0.47);
See Also