Band-gap renormalization and effective mass in double quantum wells

The band-gap and mass renormalization in the n-type doped GaAs-based double-quantum-well systems are investigated. Using the GW method within the full random-phase approximation the change in the self-energy has been computed. Numerical results for different density parameter and spacing, for double quantum wells are presented. The effect of impurity is also considered by using Mermin expression. Our results indicate that increasing the impurities and decreasing the spacing in double-layer system have opposite effects on the band-gap renormalization. We show how this effect can be utilized to offset the effect of impurity in related devices.