I found this sentence:
GaAs at 300K contains 10^15 acceptor atoms per cubic centimeter.
The bandgaps for Gallium Arsenite are:
0 Kelvin : 1.518 eV 300 Kelvin: 1.424 eV
Now I am wondering:
Why does Gallium Arsenite have this impurity?
Is the bandgap at 300 Kelvin is stated for a pure GaAs semiconductor or does it already incorporate the influence of the impurity?
If it doesn't what else does then cause the narrowing of the bandgap?