Concentration-dependent band offset inInxGa1−xAsGaAsstrained quantum wells

We have used low-temperature photoluminescence (PL) spectroscopy to study $\frac{{\mathrm{In}}_x{\mathrm{Ga}}_{1-x}\mathrm{As}}{\mathrm{GaAs}}$ single and multiple quantum wells (QW's). By analyzing the polarization dependence of the PL, the QW luminescence features were shown to be due to heavy-hole-related transitions in these samples. The conduction-band offset ratio $Q_c$ was calculated and found to be dependent on the In concentration $c$. Previously contradictory values are thus shown to be consistent with each other.